fine (futagohime), rein (futagohime), fushigiboshi no futago hime, 00s, 2girls, :d, ;d, arm up, armpits, beach, bikini, blue eyes, blue hair, body blush, bracelet, casual one-piece swimsuit, clenched hand, flat chest, flip-flops, hair bobbles, hair ornament, hair ribbon, hand to own mouth, innertube, jewelry, leg lift, legs, long hair, looking at viewer, multiple girls, navel, ocean, one-piece swimsuit, one eye closed, open mouth, outdoors, parted bangs, ponytail, profile, red eyes, red hair, ribbon, sandals, scrunchie, short twintails, siblings, sidelocks, sisters, smile, standing, standing on one leg, swim ring, swimsuit, tankini, twintails, very long hair, water, waving, wavy hair, wink