1girl, arm_up, armpits, baba_arumi, bikini, brown_eyes, brown_hair, dated, fingernails, flat_chest, idolmaster, idolmaster_cinderella_girls, long_hair, navel, shadow, sidelocks, simple_background, sitting, skindentation, smile, solo, swimsuit, tachibana_arisu, upper_body, white_background, white_bikini