Onyanko Club

 was a large all-girl Japanese pop idol group in the 1980s. Some members of the group participated in spin-off groups, such as Nyangilas, Ushiroyubi Sasaregumi and Ushirogami Hikaretai. Many of the latter two groups' songs were used as theme songs of the popular 80s anime series "High School! Kimengumi" and "Tsuide ni Tonchinkan". Several big-name idols stemmed from the group; one of the best known being Shizuka Kudo. The group was produced by Hiroshi Ishida and Kazuji Kasai, both of whom were producers of Fuji TV's show "Yūyake Nyan Nyan."
History.
1985.
The group made its television debut on the first episode of Fuji TV's daily live television variety show on 1 April 1985. The show was aired from 5 p.m. to 6 p.m. Monday to Friday. In the beginning, the group consisted of nine high school girls and two high school graduates, namely Sayuri Kokusho (number 8) and Satomi Fukunaga (number 11). They were selected from participants in two special episodes of Fuji TV's weekly late-night show "All Night Fuji." The two episodes entitled were produced as pilots of the show "Yūyake Nyan Nyan" and aired on 23 February and 16 March 1985. "Yūyake Nyan Nyan" had a segment where five candidates participated in a five-day long audition for becoming a new Onyanko Club member. Most of the Onynako Club members except the first 11 members and other members who joined the group through the 1986 Miss Seventeen Contest were admitted to the group by winning the audition. 
In less than three weeks from the launch of the show, six members were caught in photos taken by a photographer of tabloid magazine "Shukan Bunshun" while they were smoking in a kissaten (Japanese-style café) near Fuji TV's old headquarters in Shinjuku, Tokyo. They stopped appearing on the show from 18 April. Eventually, five of them were officially dismissed from the group without announcement as a result of underage smoking as of 25 April; one member was not smoking in the incident.
The group's debut single "Sailor Fuku o Nugasanai de" was premiered on "Yūyake Nyan Nyan" on 3 June. Lead vocalists (hereinafter referred to as "front vocals") for the single were Eri Nitta (number 4), Miharu Nakajima (number 5), Satomi Fukunaga and Kazuko Utsumi (number 13). Released by Canyon Records on 5 July, the single debuted at number 34 on the Oricon's Japanese single chart (the national single chart) and peaked at number five in its sixth week of release in August. A day before the single's release date, a release and handshake event was scheduled at Sunshine City in Ikebukuro, Tokyo. The event was expected to have an attendance of about 500 people. However, over 4,000 people showed up at the site. As a result of reported injury and concerns over possible stampede, the event was canceled at the last minute before a scheduled start time. In the same month, the group's member Sonoko Kawai (number 12) made her appearance as a supporting character in the episodes 11 and 12 of Fuji TV's live-action TV series "Sukeban Deka". Subsequently, it was announced on "Yūyake Nyan Nyan" that Kawai's first solo single would be released in September. The single "Namida no Jasmine LOVE" and its B-side "Koi no Chapter A to Z" were premiered on "Yūyake Nyan Nyan" on August 12 and August 19, respectively. The B-side features four Onyanko Club members as backing vocals: Sayuri Kokusho, Mika Nagoya (number 9), Mamiko Takai (number 16) and Sanae Jounouchi (number 17). In late August, producers of the show "Yūyake Nyan Nyan" teamed up with producers of the live-action TV series "Sukeban Deka" and held a special audition on "Yūyake Nyan Nyan" to look for a new Onyanko Club member who would play a main character in a sequel to the TV series. The winner of the audition was Akie Yoshizawa, who was assigned number 25. A day before the release of Kawai's first single, a release event entitled "Nyan Touch Love Party" for the single was held at Yomiuri Land EAST in Inagi, Tokyo on August 31.
Released by CBS/Sony Records on 1 September, Kawai's first single debuted at number five on the chart and topped the chart for the following two consecutive weeks. On 21 September, the group's first studio album "Kick Off" was released by Canyon Records. The album was directed by Hiroshi Watanabe (music producer) and contained 10 songs whose music was composed by several musicians, such as Jun Sato, Ken Takahashi, Etsuko Yamakawa, Kiyonori Matsuo and Tsugutoshi Goto, who all composed most of the group's and members' songs thereafter. All lyrics of the album were written by Yasushi Akimoto. The album reached number two on the Oricon's Japanese album chart and remained in the top 100 for 30 weeks. On 30 September, the group's first subgroup Ushiroyubi Sasaregumi made its television debut on "Yūyake Nyan Nyan". Its members were Mamiko Takai and Yukiko Iwai (number 19). 
The official fan club "Konyanko Club" run by Fujipacific Music was launched on 1 October. The number of fan club members peaked at about 190,000 during its operation. On 5 October, Onyanko Club had its first concert entitled "Kick Off" at Hibiya Yagai Ongakudo in Chiyoda, Tokyo. It was recorded and released as a video by Pony Inc. in the following month. On the same day as the first concert, Ushiroyubi Sasaregumi's first single "Ushiroyubi Sasaregumi" was released by Canyon Records. The single and its B-side were used as the opening theme and ending theme, respectively, of Fuji TV's anime "High School! Kimengumi", which was adaptation from the manga series. One of the reasons why Takai and Iwai were selected for the subgroup was that their images matched the anime's two girl characters named Kawa Yui and Uru Chie. Originally the subgroup was named "Kiwi-Gumi". 30,000 copies of the first single's front cover insert were printed with the name before a producer of "Yūyake Nyan Nyan" decided to change it to Ushiroyubi Sasaregumi. The first single peaked at number five on the Japanese single chart. On 21 October, Onyanko Club's second single "Oyoshi ni Natte ne Teacher" was released by Canyon Records. It debuted at number two on the single chart. 
On 1 November, Yoshizawa's first solo single "Naze? no Arashi" was released by For Life Records under the name of "Yoshizawa Akie with Onyanko Club". Four Onyanko Club members Aki Kihara (number 6), Mika Nagoya, Harumi Tomikawa (number 14) and Ruriko Nagata (number 18) were selected as backing vocals for the single. Although their backing vocals actually were not recorded in the single, the members were pictured on the back cover of the 7-inch single and always performed with Yoshizawa on "Yūyake Nyan Nyan" and in the single release events as well as Onyanko Club's concerts. The song was used as the ending theme of Fuji TV's live-action TV series "Sukeban Deka II: Shōjo Tekkamen Densetsu" for the episodes 1 to 15. Yoshizawa played one of the three main characters of the TV series aired from 7 November 1985, to 23 October 1986. The single peaked at number eight on the single chart.
In the fall and winter of 1985, Kawai expanded her solo activities with her second single "Ochiba no Crescendo" released on 21 November and her first solo album "Sonoko" released on 5 December both by CBS/Sony Records. She also started appearing as a supporting character in Fuji TV's drama TV series "The Mirror of Janus" (ヤヌスの鏡), which was adaptation from the manga series, aired from 4 December 1985, to 16 April 1986, and had her first solo concert at Gold Hall at Shinagawa Prince Hotel in Shinagawa, Tokyo on 28 December. The concert was recorded and released as a video by CBS/Sony Home Video in March 1986.
1986.
Premiered on "Yūyake Nyan Nyan" on 16 December 1985, and released by Canyon Records on 1 January 1986, Onyanko Club member number 4 Eri Nitta's first solo single "Fuyu no Operagrasu" debuted at number one on the single chart and remained number one for the four consecutive weeks. The number of its sales exceeded that of any of Onyanko Club-related singles released earlier. On 21 January, Ushiroyubi Sasaregumi's second single "Banana no Namida" was released by Canyon Records. It debuted at number one on the single chart and was used as the ending theme of Fuji TV's anime "High School! Kimengumi". In the same month, Onyanko Club member number 8 Sayuri Kokusho started performing her first solo single "Valentine Kiss" on "Yūyake Nyan Nyan". Two Onyanko Club members Mako Shiraishi (number 22) and Minayo Watanabe (number 29) were selected as backing vocals for the single. Released by CBS/Sony Records under the name of "Kokusho Sayuri with Onyanko Club" on 1 February, the single debuted at number two on the single chart. 
In February, it was announced on "Yūyake Nyan Nyan" that the group's two members Miharu Nakajima and Sonoko Kawai would "graduate" from the group in April. Nakajima decided to retire from the music and entertainment industry and go to college for becoming a dental hygienist while Kawai would move on to pursue her solo career as a singer and later a singer-songwriter. Japanese word "sotsugyou (卒業)", which means "graduation (from school)", was used by the group for the first time in the Japanese pop music industry to describe departure of members from an idol group or a band. The reason for the use of the Japanese word was that the group and its activities were revolving around a concept that it was a student club that engaged in show business activities as extracurricular activities. As one of the rules for Onyanko Club members, they had to attend high school and maintain good grades to be able to remain in the group. There were members who were dismissed from the group by producers of "Yūyake Nyan Nyan" in violation of the rule by quitting school. Members also had to take their time off from appearing on the daily TV show and participating in other activities of the group during their respective schools' midterm exams and final exams as well as during times for exam preparation.
Onyanko Club's third single "Jā ne" was released by Canyon Records on 21 February. It was named after Japanese word "jā ne (じゃあね)", which is a casual way of saying "goodbye", and was a farewell song to Nakajima, who was leaving the group in April. Moreover, it was originally planned to be released under the name of "Nakajima Miharu with Onyanko Club" as her first and last solo single. However, Nakajima suggested releasing it as the group's third single. It debuted at number one on the single chart. On 1 March, Yoshizawa's second single "Kisetsu Hazure no Koi" was released by For Life Records. It topped the single chart for two consecutive weeks. The B-side of the single is "Kaiin Bangou no Uta", which literally means "The Song of Membership Numbers". It was performed by and recorded with all 22 remaining members of Onyanko Club at that time. The song is credited to Onyanko Club and consists of four choruses and 22 verses, each verse sung by each member individually about herself for approximately 14 seconds. The music of the song was composed by Akira Mitake, who composed many of the group's and members' songs. The lyrics of the song was written by Yasushi Akimoto. On 10 March, the group's second studio album "Yume Catalogue" was released by Canyon Records. It topped the Oricon's Japanese album chart. The second album features songs sung by various combinations of members, some of whom had solo vocal parts for the first time in the group's recordings, such as "Suki ni Nattemo Kurenai" sung by Aki Kihara, Mika Nagoya and Rika Tatsumi (number 15) and "Ren'ai Omimai Moushiagemasu" sung by Harumi Tomikawa, Sanae Jounouchi and Ruriko Nagata.
The group's first nationwide concert tour began at Hokkaido Kosei Nenkin Kaikan in Sapporo, Hokkaido on 16 March. Subsequently they performed in Hiroshima, Nagoya, Sendai, Osaka and Tokyo and had 14 shows in total with a total of 96,673 attendees in the whole tour. Tickets of the first concert tour didn't get to general sale as they were sold out to fan club "Konyanko Club" members only. On 21 March, Kawai's third single "Aoi Stashion" was released by CBS/Sony Records. It topped the single chart for two consecutive weeks and eventually became the most successful single out of all of the group's and member's singles released while the group was active. On "Yūyake Nyan Nyan" aired on 31 March, a "graduation ceremony" for Nakajima and Kawai was held, which was recorded earlier as on the same day the group was having two shows a day at Nippon Budokan in Tokyo as part of the nationwide concert tour. On 1 April, which was the final date of the tour, Nakajima and Kawai concluded their activities as Onyanko Club members with three shows a day at Nippon Budokan. The concert at Nippon Budokan was recorded and aired on Fuji TV on 5 April as well as released as a video by Pony Inc. in May 1986.
On the same day as the final date of the concert tour, Nyangilas' first single "Watashi wa Rika-chan" was released by Warner-Pioneer. The subgroup's members were Aki Kihara, Mika Nagoya, Rika Tatsumi and Mako Shiraishi. Prior to the subgroup formation, there was a segment on "Yūyake Nyan Nyan" aired in November 1985 where the show's hosts and panelists had a debate over whether Kihara, Nagoya and Tatsumi should form a subgroup and have their own songs for release. Although the three members were up for the idea, at that time it was generally perceived that they were not good singers or exceptionally popular members compared to other members, such as Sonoko Kawai and Eri Nitta. At the same time they were perceived as more humorous and cheerful than other members. Among the panelists, Yasushi Akimoto, who later wrote lyrics of all of Nyangilas' songs including its album songs, supported the idea, and eventually producers of "Yūyake Nyan Nyan" decided to make it happen with Shiraishi added, who they thought would make the subgroup more appealing to wider audiences. The first single was released on April Fools' Day, which was intended as a joke, and went straight to number one on the single chart, keeping popular Japanese boy band Shonentai's much anticipated second single off from the number-one spot. Tatsumi later said that as both singles were released by the same record label, the boy band's A&R executive got mad at her and her bandmates, saying that the boy band was supposed to get the number-one spot.
Nitta's second single "Koi no Rope wo Hodokanaide" was released by Canyon Records on 10 April. Originally its B-side "Pink no Ribbon" was decided to be a A-side. However, Nitta objected to it, and as a result Tsugutoshi Goto, who was the composer and arranger of both songs, had to revise "Koi no Rope wo Hodokanaide" for making it suitable for the A-side. It topped the single chart for two consecutive weeks. On 21 April, Onyanko Club's fourth single "Otto Chikan!" was released by Canyon Records. Front vocals for the single were Satomi Fukunaga, Kazuko Utsumi, Sanae Jounouchi, Ruriko Nagata and Mutsumi Yokota (number 28). It topped the single chart.
Fuji TV's weekly live television variety show "Yūshoku Nyan Nyan" starring the group and featuring presenters, one of whom was Sonoko Kawai, was launched on 2 May. It was aired from 7 p.m. to 7:30 p.m. every Friday and was very similar to "Yūyake Nyan Nyan" in their contents except that the weekly show was intended to promote Musukko Club, which was an all-boy idol group and intended as a boy version of Onyanko Club. It was short-lived and lasted until 19 September. In the same month, Ushiroyubi Sasaregumi's third single "Zousan no Sukyantee" and Sayuri Kokusho's second single "Natsu wo Matenai" were released by Canyon Records and CBS/Sony Records, respectively. Both singles topped the single chart.
Satomi Fukunaga's first solo single "Kaze no Invitation" was released by Canyon Records on 21 May. Prior to her performance of the song for promotion on "Yūyake Nyan Nyan" since the mid-May, it had already been premiered two months earlier during the group's first nationwide tour in March. On 25 May, a release event entitled "Satomi Invitation" for the single was held at Yomiuri Land EAST with a total of about 6,500 attendees, 1,500 of whom were lining up overnight for entry. The single debuted at number one on the single chart. 
Onyanko Club member number 17 Sanae Jounouchi's first solo single "Ajisai Bashi" was released by CBS/Sony Records on 11 June. The single was categorized as enka, which is a Japanese music genre and considered as traditional Japanese popular music as opposed to other music genres influenced by Western pop and rock music. It debuted at number one on the Oricon's Japanese single chart. It was the first instance in the chart's history that a single in the category of enka went straight to number one on the single chart in the first week of release. As of 2021 the single remains as the only debut single in the category of enka that debuted at number one on the single chart. 
Nyangilas' second single "Jibun de Yuunomo Nandesukeredo" was released by Warner-Pioneer on 21 June. It went straight to number one on the single chart, making all of Nyangilas' singles number-one singles. On 25 June, Mamiko Takai's first solo single "Cinderella-tachi e no Dengon" was released by Canyon Records while she still was the member of Ushiroyubi Sasaregumi. It debuted at number one on the single chart. 
Onyanko Club member number 29 Minayo Watanabe's first solo single "Hitomi ni Yakusoku" was premiered on "Yūyake Nyan Nyan" on 2 July. A release event entitled "The First and Last Touch in Budokan" for the single was held at Nippon Budokan with a total of about 12,000 attendees on 5 July. On 10 July, Onyanko Club's third album "Panic the World" was released as a double album by Canyon Records. It consists of the original studio album with 10 newly released songs and a greatest hits compilation album with 11 songs previously released by Canyon Records, CBS/Sony Records, For Life Records and Warner-Pioneer. The double album reached number three on the Oricon's album chart. Meanwhile, Watanabe's first single was released by CBS/Sony Records on 16 July and debuted at number one on the single chart.
The group's second nationwide concert tour entitled "Onyanko Panic" began at Yokohama Stadium in Yokohama, Kanagawa on 19 July. In the stadium concert, the group announced on stage that five members Eri Nitta, Mika Nagoya, Satomi Fukunaga, Akie Yoshizawa and Kumiko Susan Yamamoto (number 32) would "graduate" from the group in September. Nitta, Nagoya, Fukunaga and Yoshizawa would move on to pursue their solo careers as a singer and/or actress while Yamamoto decided to retire from the music and entertainment industry and finish college. On 21 and 22 July, the group had more stadium concerts at Hankyu Nishinomiya Stadium in Nishinomiya, Hyogo. For the second tour, they subsequently performed in Hiroshima, Nagoya, Shizuoka, Fukuoka, Niigata, Fukui, Nagano, Sendai and Sapporo in August and in Tokyo in September. On 21 July, Onyanko Club's fifth single "Osaki ni Shitsurei" was released by Canyon Records. Front vocals for the single were Harumi Tomikawa, Yukiko Iwai, Tomoko Fukawa (number 33) and Marina Watanabe (number 36). The single went straight to number one on the single chart.
Onyanko Club's movie "Onyanko the Movie: Kiki Ippatsu!" starring all members as the group was released in theaters nationwide by Toho Pictures on 23 August. It was directed by Masato Harada and played as a double feature with film "Sorobanzuku" starring Japanese comedy duo Tunnels, who also was a regular on "Yūyake Nyan Nyan". The group's film includes scenes from the concert at Yokohama Stadium, rehearsals and backstage. 
Fukunaga's second solo single "Heart no Ignition" was premiered on the weekly show "Yūshoku Nyan Nyan" on 12 September. The song was used as the ending theme of Fuji TV's live-action TV series "Sukeban Deka III: Shōjo Ninpō-chō Denki" for the episodes 1 to 8. Fukunaga played a supporting character in the episodes 1 to 20 of the TV series, which had a total of 42 episodes aired from 30 October 1986, to 29 October 1987. Released by Canyon Records on 1 October 1986, the single peaked at number two on the single chart.
On "Yūyake Nyan Nyan" aired on 26 September, a "graduation ceremony" for Nitta, Nagoya, Fukunaga, Yoshizawa and Yamamoto was held. It was recorded earlier as on the same day the group was having concerts at Nippon Budokan in Tokyo as part of the second nationwide concert tour. On 25 and 26 September, which were the final dates of the tour, Nitta, Nagoya, Fukunaga, Yoshizawa and Yamamoto concluded their activities as Onyanko Club members with the group's concerts at Nippon Budokan. Also, the subgroup Nyangilas disbanded as a result of Nagoya's departure from Onyanko Club. The concert on 26 September was recorded and aired on Fuji TV on 3 November as well as released as a DVD in October 2003 by Pony Canyon. 
In September, Onyanko Club B-Gumi, which was a junior version of Onynako Club and consisted of junior high school girls, was formed. "B-Gumi" means "class B". The members were Mitsuko Yoshimi (B-Gumi number 1), Miyuki Sugiura (B-Gumi number 2), Kumiko Miyano (B-Gumi number 3) and Hiroko Tominaga (B-Gumi number 4), all of whom were runners-up of the 1986 Miss Seventeen Contest held in August, as well as Mayumi Yamazaki (B-Gumi number 5), who won a weekly audition on the TV show "Yūyake Nyan Nyan" on 25 September. The group made its television debut on the show on 29 September.
Onyanko Club member number 36 Marina Watanabe's first solo single "Shinkokyu shite" was released by Epic/Sony Records under the name of "Watanabe Marina with Onyanko Club" on 8 October. Two Onyanko Club members Shizuka Kudo (number 38) and Akiko Ikuina (number 40) were selected as backing vocals for the single. It debuted at number one on the Oricon's Japanese single chart. In the chart's history at that time, she became the youngest female singer at her age of 15 years and 11 months who had a debut single that went straight to number one on the single chart in the first week of release. This record was not broken for 14 years and five months.
Onyanko Club's sixth single "Koi wa Question" was released by Canyon Records on 1 November. Front vocals for the single were Yukiko Iwai, Ruriko Nagata, Mako Shiraishi and Akiko Ikuina. The single and its B-side were used as the opening theme and ending theme, respectively, of Fuji TV's anime "Anmitsu Hime" aired from 5 October 1986, to 27 September 1987. The single topped the single chart.
Onyanko Club member number 13 Kazuko Utsumi's first solo single "Aoi Memories" was released by Canyon Records on 7 November. The single and its B-side were used as part of the soundtrack to Fuji TV's anime "Touch", which was adaptation from the manga series. The single debuted at number three on the single chart. Prior to joining Onyanko Club, Utsumi used to be a child actress in the 70s and early 80s and made many one-off appearances on TV drama series and live-action series, such as "Kamen Rider Super-1" (episode 3) and "Chojin Barom-1" (episode 32) to name few. She also attended a music school established by Masaaki Hirao, who was a critically acclaimed singer-songwriter and music producer in the Japanese pop music industry, and took vocal lessons in the pre-Onyanko Club years. It was one of the reasons why she had many lead vocal parts in the group's earlier recordings.
Compilation album "Merry X'mas for You" was released by CBS/Sony records on 5 December. It contains six songs and consists of newly released song "Merry X'mas for You" sung together by CBS/Sony Records artists Sonoko Kawai, Sayuri Kokusho, Sanae Jounouchi and Minayo Watanabe as well as Epic/Sony Records artist Marina Watanabe, and five previously released songs, each sung individually by them. The album reached number three on the Oricon's Japanese album chart. In the meantime, television advertisements featuring Onyanko Club member number 40 Akiko Ikuina for Japanese convenience store Lawson's chicken nugget product "Karaage Kun" were premiered on-air on 8 December. In the advertisements, song "Heart ni Bokin wo" was used. At that time, it was generally expected by fans that the song would be released as Ikuina's debut solo single because her name was credited as the singer for the song in the ad and also because the version used in the ad was sung by Ikuina only. However, it later ended up being re-recorded/re-produced as the group's song and released as one of the eleven songs on Onyanko Club's fourth studio album "Side Line" in early 1987.
As part of her first solo concert tour entitled "E-AREA", Eri Nitta had a concert at Nippon Budokan on 18 December. A concert at Nakano Sun Plaza in Nakao, Tokyo on 3 November for the concert tour was recorded and released as a video by Pony Inc. in January 1987. Sayuri Kokusho also had a concert at Ryougoku Kokugikan in Sumida, Tokyo on 24 December as the final show of her first solo concert tour entitled "Dash Kokusho!" It was recorded and released as a video by CBS/Sony Home Video in April 1987.
On "Yūyake Nyan Nyan" aired on 25 December, a "graduation ceremony" for Mami Yumioka (number 34), Takako Okamoto (number 35) and Maki Takabatake (number 39) was held. All the three members decided to retire from the music and entertainment industry. Okamoto later said in an interview that she initially was interested in the music and entertainment industry but felt she didn't have confidence in pursuing a solo career as an entertainer in the future and wanted to live an ordinary life as a high school student like most people do.
By the end of 1986, singles of the group, its members, "graduated" members and subgroups topped the Oricon's Japanese single chart in 36 weeks out of the 52 weeks. Out of the total 46 singles that topped the chart during 1986, 30 singles were Onyanko Club-related ones. All of their studio albums released in the same year were successful on the Oricon's Japanese album chart as well, with the group's second album "Yume Catalogue", Nitta's first solo album "ERI" and Kawai's two albums "Siesta" and "Mode de Sonoko" all having reached number one on the album chart.
1987.
On "Yūyake Nyan Nyan" aired on 5 January, it was announced that the group's five members Aki Kihara, Sayuri Kokusho, Kazuko Utsumi, Rika Tatsumi and Mamiko Takai would "graduate" from the group in April. Kokusho, Utsumi and Takai would move on to pursue their solo careers while Kihara and Tatsumi decided to retire from the music and entertainment industry. Onyanko Club's seventh single "No More Ren'ai Gokko" was premiered on "Yūyake Nyan Nyan" on 9 January. Front vocals for the single were Harumi Tomikawa, Ruriko Nagata, Yukiko Iwai and Mako Shiraishi. Released by Canyon Records on 21 January, the single debuted at number one on the single chart. On the same day as the single's release date, Mamiko Takai's first solo album "Itoguchi", which contains her first three singles released in the previous year, was released by Canyon Records. It debuted at number one on the Oricon's Japanese album chart.
Ushiroyubi Sasaregumi's sixth and last single "Kashiko" was released by Canyon Records on 21 February. It topped the single chart and became the subgroup's fifth consecutive single to reach number one on the chart. The single and its B-side were used as the opening theme and ending theme, respectively, of Fuji TV's anime "High School! Kimengumi". On the same day as the release date of the subgroup's last single, Onyanko Club's fourth studio album "Side Line" was released by Canyon Records. The album features songs in which newer members, such as Shizuka Kudo, Noriko Kaise (number 41) and Makiko Saito (number 42), had solo vocal parts for the first time in the group's recordings, such as "Dare no Seikana" sung by Iwai, Kudo and Ikuina and "One-side Game" sung by Shiraishi, Ikuina, Kaise and Saito as front vocals. Five days after the release of the group's fourth album, Marina Watanabe's first solo album "MARINA" was released by Epic/Sony Records on 26 February. Both albums topped the album chart. Prior to the release of Watanabe's first solo album, a release event entitled "Sweet Little Sixteen" for the album was held at Nippon Budokan on 15 February with a total of about 10,000 attendees who pre-ordered the album and won tickets to the event.
Ushiroyubi Sasaregumi's compilation album formula_1 ("Unlimited") was released by Canyon Records on 11 March. The album consists of all of its six singles, the sixth single's B-side and four previously unreleased songs. It topped the album chart. With a little less than a month before Ushiroyubi Sasaregumi would disband as a result of Mamiko Takai's departure from Onyanko Club, Takai's fourth solo single "Kagerou" and another Ushiroyubi Sasaregumi member Yukiko Iwai's first solo single "Tenshi no Bodyguard" were premiered on "Yūyake Nyan Nyan" on 9 March. On the same day, Onyanko Club member number 15 Rika Tatsumi's first and last solo single "Sonna Tsumorija Nakattanoni" was premiered on the show as well. Takai's fourth single released by Canyon Records and Tatsumi's first single released by Warner-Pioneer both on 18 March reached number one and number 34 on the single chart, respectively. Two days later, a "graduation ceremony" for four Onyanko Club members Toshie Moriya (number 43), Naoko Takada (number 44), Yumiko Yoshida (number 45) and Sanae Nakajima (number 46) as well as two Onyanko Club B-Gumi members Hiroko Tominaga (B-Gumi number 4) and Mayumi Yamazaki (B-Gumi number 5) was held on "Yūyake Nyan Nyan" on 20 March. Their "graduation" was not announced in advance, and also their specific reasons for leaving the group were not revealed. Although some of the members continued to pursue their careers in the music and entertainment industry, they eventually faded out from the industry or went under the radar except Yamazaki, who had four solo singles released between 1988 and 1992.
The first solo single of Iwai, whose nickname was "Yuuyu", was released by Canyon Records under the name of "Yuuyu with Onyanko Club" on 25 March. Three Onyanko Club members Ruriko Nagata, Mutsumi Yokota and Tomoko Fukawa were selected as backing vocals for the single. It debuted at number two on the single chart. On 28 March, the group's third nationwide concert tour entitled "Onyanko Sailing Yumekoujyou" began at Osaka-jo Hall in Osaka. They subsequently performed at arenas in Fukuoka, Nagoya and Tokyo. The whole tour drew a total of some 200,000 attendees.
On "Yūyake Nyan Nyan" aired on 30 March, a "graduation ceremony" for Kihara, Kokusho, Utsumi, Tatsumi and Takai was held. On 4 and 5 April, which were the final dates of the tour, Kihara, Kokusho, Utsumi, Tatsumi and Takai concluded their activities as Onyanko Club members with the group's concerts at Yoyogi National Gymnasium in Shibuya, Tokyo. The concerts were recorded and released as a video by Pony Inc. in May. Also on 3 June, live album "Onyanko Sailing Yumekoujyou '87 LIVE" of the concerts was released in three formats: vinyl, cassette and compact disc, which were released by Canyon Records, Epic/Sony Records and CBS/Sony Records, respectively. The album in each format contains a slightly different set of tracks.
As a new school year started in April, Onyanko Club B-Gumi members Mitsuko Yoshimi (B-Gumi number 1), Miyuki Sugiura (B-Gumi number 2) and Kumiko Miyano (B-Gumi number 3), who all became high school students, were advanced to Onyanko Club on 6 April. Yoshimi, Sugiura and Miyano were assigned numbers 49, 50 and 51, respectively. Prior to the advancement, they participated in Onyanko Club's third nationwide concert tour in March and April and made their concert debut.
Onyanko Club's third subgroup Ushirogami Hikaretai started performing its first single "Toki no Kawa wo Koete" on "Yūyake Nyan Nyan" on 13 April. Its members were Shizuka Kudo, Akiko Ikuina and Makiko Saito. It was formed as a successor to Ushiroyubi Sasaregumi, which disbanded on the final date of Onyanko Club's concert tour earlier in the same month. Like Ushiroyubi Sasaregumi's singles, the first single of Ushirogami Hikaretai and its B-side, with music composed by Tsugutoshi Goto and lyrics written by Yasushi Akimoto, were used as the opening theme and ending theme, respectively, of Fuji TV's anime "High School! Kimengumi". In the meantime, Wakako Suzuki won a weekly audition on "Yūyake Nyan Nyan" on 17 April and became the 52nd Onyanko Club member. Within the following two months it turned out that she was the last member to join the group. Onyanko Club's eighth single "Katatsumuri Samba" was premiered on "Yūyake Nyan Nyan" on 28 April. Front vocals for the single were Harumi Tomikawa, Shizuka Kudo, Mitsuko Yoshimi (number 49) and Miyuki Sugiura (number 50). Ushirogami Hikaretai's first single released on 7 May and Onyanko Club's eighth single released on 21 May both by Canyon Records debuted at number one on the single chart. On 7 May, "Yūyake Nyan Nyan"'s 500th episode was aired.
On "Yūyake Nyan Nyan" aired on 15 June, it was announced that Onyanko Club would disband after its final concert in September and that "Yūyake Nyan Nyan"'s final episode would be aired on 31 August. In the following month, Marina Watanabe's fourth single "Natsuyasumi Dakeno Side Seat" was released by Epic/Sony Records on 15 July. Two weeks later, Minayo Watanabe's fifth single "Amaryllis" was released by CBS/Sony Records on 29 July. Both singles topped the chart. "Amaryllis" became Minayo Watanabe's fifth consecutive single that debuted at number one on the chart. In the chart's history as of 2021, she is the only female singer who has the five consecutive number-one singles since her solo debut.
Released by Canyon Records on 29 July, Yukiko Iwai's first solo album "Yuuyu Kousen" debuted at number one on the Oricon's LP chart. A week later, Onyanko Club's fifth and final studio album "Circle" was released as a double album by Kirigirisu Records on 5 August. The first disc consists of 14 newly released songs: four songs sung individually by the group's four members who made their solo debut earlier, seven songs sung individually by seven "graduated" members, one song sung by the subgroup Ushirogami Hikaretai and two instrumentals. The second disc contains 12 newly released songs sung by various combinations of the group's members. The double album reached number two on the Oricon's album chart.
The group's fourth and final nationwide concert tour entitled "Onyanko Club Kaisan Kinen Zenkoku Jyudan Final Concert" began at Hokkaido Kosei Nenkin Kaikan in Sapporo, Hokkaido on 1 August. Subsequently they performed in Hiroshima, Fukuoka, Nagoya, Fukui, Nagoya (the second visit), Kooriyama, Niigata, Nagano and Osaka in August and in Tokyo in September. At concerts in each of the cities except Tokyo, one to four "graduated" members made guest appearances and performed a few of their own songs.
On 12 August, Ushirogami Hikaretai's second single "Anata wo Shiritai" was released by Canyon Records. The single and its B-side were used as the opening theme and ending theme, respectively, of Fuji TV's anime "High School! Kimengumi". It debuted at number two on the single chart. Two days before the release of Ushirogami Hikaretai's second single, Onyanko Club's ninth single "Wedding Dress" was premiered on "Yūyake Nyan Nyan" on 10 August. Front vocals for the single were Harumi Tomikawa, Ruriko Nagata, Mako Shiraishi, Mutsumi Yokota and Tomoko Fukawa. Released by Kirigirisu Records on 21 August, the single debuted at number two on the single chart.
After two years and five months of its run, the show "Yūyake Nyan Nyan" was ended with an extended two-hour live broadcast on 31 August. Most of past Onyanko Club members except dismissed members made their appearance on the final episode. Also, a "graduation ceremony" for the 19 remaining members was held. On the same day as the show's finale, Shizuka Kudo's first solo single "Kindan no Telepathy" was released by Canyon Records. It debuted at number one on the single chart. The group concluded its activities with its final concerts at Yoyogi National Gymnasium in Shibuya, Tokyo on 19 and 20 September. They had two shows a day on the 19th and three shows a day on the 20th. At the final concerts, 11 "graduated" members reunited with the remaining members on stage and performed a few of the group's songs together toward the end of each show as well as "graduated" members' songs. Part of the afternoon show on the 20th was broadcast live on Fuji TV. The whole evening show on the 20th was recorded and released as a video by Pony Canyon on 31 October. By the time of the disbandment, 43 of 71 singles of the group, its members, "graduated" members and subgroups topped the Oricon's Japanese single chart.
Post-disbandment.
Members who had their solo singles and/or albums earlier and the subgroup Ushirogami Hikaretai continued to expand their activities with more music releases and media appearances. Several members had their first solo singles after the disbandment. On 21 November 1987, Onyanko Club member number 48 Kayo Agatsuma's first solo single "Private wa Dangerous" was released by CBS/Sony Records. It reached number nine on the single chart. Onyanko Club B-Gumi member number 5 Mayumi Yamazaki's first solo single "Hitomi wo Mitsumete" was released by Polydor Records (Japan) on 1 April 1988. Ushirogami Hikaretai member Akiko Ikuina's first solo single "Mugiwara de Dance" was released by Pony Canyon on 21 May 1988. The single and its B-side were used as the opening theme and ending theme, respectively, of Fuji TV's anime "Tsuide ni Tonchinkan", which was adaptation from the manga series"." It reached number eight on the single chart. Another Ushirogami Hikaretai member Makiko Saito's first solo single "Yaritai Houdai" was released by Pony Canyon on 21 July 1988. It reached number 28 on the single chart. 
Sayuri Kokusho, Minayo Watanabe, Marina Watanabe and Akiko Ikuina went on to have successful careers as an actress, singer and/or TV personality throughout the remainder of the decade and 1990s, appearing on variety TV shows and films. Sanae Jounouchi continued having music releases constantly and a successful career as an enka singer. All of them are active in the entertainment industry as of 2021.
Shizuka Kudo went on to have chart-topping hits in the 80s and 90s. Rika Tatsumi graduated from Tokai University and launched a career as a sales representative at Pony Canyon promoting artists' releases including Kudo's in the Tokyo and Nagoya areas.
Eri Nitta found a career as a writer and columnist after retiring into private life in 1990. She later re-entered the show business as a TV personality in 1993. Miharu Nakajima continued working as a dental hygienist before getting married in 1997. Aki Kihara and Mika Nagoya moved to the Netherlands and Hong Kong, respectively, to study and work. They eventually got married and settled in the country and region, respectively. Harumi Tomikawa became a water sports instructor at JAL Private Resort Okuma in Okinawa. Kumiko Susan Yamamoto graduated from Bunkyo Gakuin College and has worked for group companies of the Central Japan Railway Company thereafter. Makiko Saito married the chief executive officer of the Sujahta Meiraku Group in 1998.
The group's 10th single "Shoumi Kigen", its first one in 15 years, was released by Pony Canyon on November 20, 2002. 14 members who participated in recording of the single were Nitta, Kihara, Kokusho, Nagoya, Utsumi, Tomikawa, Tatsumi, Jounouchi, Iwai, Shiraishi, Yokota, Minayo Watanabe, Yamamoto and Fukawa. The new release project came along in response to good sales of five-disc DVD box set "Onyanko Club Saishuu-ban: The Final Episode" released by Pony Canyon on April 17, 2002. More members, namely Yumioka, Okamoto, Kaise, Yuriko Yamamori (number 47), Agatsuma, Sugiura and Miyano, joined the reunion for performances of the single on TV shows around the time of the single's release.
Onyanko Club's 126-CD box set "Kessei Sanjyusshuunen Kinen CD-BOX Single Record Fukkoku Nyan Nyan" (結成30周年記念CD-BOX シングルレコード復刻ニャンニャン) was released by Pony Canyon on March 18, 2015 to commemorate the 30th anniversary of the group's formation. It includes all of the group's, three subgroups' and 16 members' singles released by Canyon Records, CBS/Sony Records, Epic/Sony Records, For Life Records and Warner-Pioneer between July 5, 1985 and September 6, 1989. Each of the 7-inch singles was replicated as a 12-cm compact disc with a scaled-down original front cover insert or sleeve, inner paper sleeve and inner plastic sleeve. Each CD contains an A-side and B-side of a single as well as their instrumental (karaoke) tracks, except for the "Merry X'mas for You" bonus CD, which contains only the song and its instrumental track. There are 251 songs and their 251 instrumental versions on 126 CDs. Additionally some CDs include extra audio tracks spoken by members. The box set was limited to pre-order by January 16, 2015 although a small number of copies went on general sale after the release date. 
There have been several reunion appearances, including one on an episode of "Hey! Hey! Hey! Music Champ" in 2012.
Members.
Listed in order of joining Onyanko Club. Members 1 to 11 were the original members of the group when it started on 1 April 1985, and were assigned member numbers randomly. Subsequent members of the group were assigned numbers based on the order of their joining. Members 12 to 16 joined during April 1985.
Subgroups.
Ushiroyubi Sasaregumi.
 was the first subgroup with Mamiko Takai (#16) and Yukiko Iwai aka "Yuuyu" (#19) and released six singles and three albums from 1985 to 1987.
Nyangilas.
 was the second of three offshoot groups within Onyanko Club. They had the shortest run with only two singles and one album. Members consisted of Aki Kihara (#6), Mika Nagoya (#9), Rika Tatsumi (#15) and Mako Shiraishi (#22).
Ushirogami Hikaretai.
 consisted of Shizuka Kudo (#38), Akiko Ikuina (#40) and Makiko Saito (#42) and released five singles, two studio albums and one live album in 1987 and 1988.