1girl, arm_support, bad_twitter_id, bare_shoulders, beach, bikini, black_bikini, blonde_hair, blue_eyes, breasts, cleavage, dated, halterneck, idolmaster, idolmaster_cinderella_girls, knee_up, lamp_p9, large_breasts, leaning_back, long_hair, looking_at_viewer, navel, ocean, ohtsuki_yui, open_mouth, outdoors, signature, sitting, sky, smile, solo, swept_bangs, swimsuit, wavy_hair