1boy, 1girl, air_bubble, anthias_(fish), barefoot, bikini, bikini_top_only, black_hair, black_male_swimwear, blue_eyes, bubble, butterflyfish, closed_mouth, collarbone, fish, full_body, katou_kaisei, looking_at_viewer, male_swimwear, medium_hair, mermaid, mizushima_aimi, monster_girl, navel, open_mouth, original, pink_bikini, purple_eyes, rinshi, short_hair, starfish, string, string_of_fate, swim_trunks, swimsuit, topless_male, tropical_fish, underwater