1girl beach bikini blue_bikini blue_hair blue_sky breasts cleavage crab dark_blue_hair day holding holding_innertube idolmaster idolmaster_million_live! idolmaster_million_live!_theater_days innertube jewelry kwaejina large_breasts looking_at_viewer navel necklace open_mouth outdoors short_hair sky solo swimsuit toyokawa_fuka wavy_hair