1girl, animal_ears, ass, black_one-piece_swimsuit, breasts, brown_hair, competition_swimsuit, cowboy_shot, from_behind, highleg, highleg_swimsuit, horse_ears, horse_girl, horse_tail, indoors, long_hair, looking_at_viewer, looking_back, mejiro_dober_(umamusume), one-piece_swimsuit, pool, purple_eyes, solo, swimsuit, tail, umamusume, waity_awa