4girls, :d, armpits, arms up, bangs, black one-piece swimsuit, blue hair, blue sky, breasts, cloud, collarbone, competition school swimsuit, covered navel, day, hair ribbon, kotonoha akane, lens flare, long hair, looking at viewer, multiple girls, one-piece swimsuit, open mouth, outdoors, pink eyes, pink hair, presenting armpit, ribbon, school swimsuit, showering, sidelocks, sky, small breasts, smile, solo focus, standing, swimsuit, taut clothes, taut swimsuit, teeth, tying hair, upper teeth only, voiceroid, wakana hanabi, wet