3girls, blush, breasts, brown_background, brown_hair, chibi, chibi_inset, cleavage, collarbone, covered_navel, crossed_arms, dot_nose, embarrassed, idolmaster, idolmaster_shiny_colors, karikura_(atatata71), kuwayama_chiyuki, long_hair, looking_at_viewer, medium_breasts, multiple_girls, name_tag, osaki_amana, osaki_tenka, school_swimsuit, siblings, simple_background, sisters, standing, sweatdrop, swept_bangs, swimsuit, twins, v, wince, yellow_eyes