1girl, ass, black_hair, blue_one-piece_swimsuit, competition_swimsuit, from_behind, gradient_background, grey_background, grey_sailor_collar, long_hair, looking_back, neckerchief, one-piece_swimsuit, original, parted_lips, red_eyes, red_neckerchief, sailor_collar, school_uniform, sebunsu, serafuku, solo, standing, swimsuit, unworn_clothes, white_background