1girl aa211108 bare_legs barefoot bikini black_hair blush breasts frilled_bikini frills idolmaster idolmaster_shiny_colors kazano_hiori knees_up looking_at_viewer lying mole mole_under_mouth navel on_back ponytail side-tie_bikini_bottom simple_background small_breasts solo stomach swimsuit upside-down wavy_hair white_background