1girl, animal_ears, bad_pixiv_id, bikini, blue_sky, breasts, cowboy_shot, day, ear_covers, green_eyes, halterneck, horse_ears, horse_girl, horse_tail, light_green_hair, medium_breasts, navel, osashimisan, outdoors, seiun_sky_(umamusume), short_hair, side-tie_bikini_bottom, single_ear_cover, sky, solo, standing, string_bikini, swimsuit, tail, umamusume, white_bikini