1girl, ahoge, beach, belly, bikini, blonde_hair, breasts, cloud, frilled_bikini, frills, green_eyes, hosizora_mikoto, idolmaster, idolmaster_cinderella_girls, long_hair, navel, ocean, open_mouth, outdoors, sky, small_breasts, solo, swimsuit, two_side_up, white_bikini, yusa_kozue