Rule 34 Dev - 1girl aged_down animal_ears backpack bag black_dress brown_hair cropped_legs dress ear_covers gentildonna_(umamusume) hair_rings horse_ears horse_girl horse_tail long_hair long_sleeves looking_at_viewer parted_lips randoseru red_eyes romi_(346_ura) simple_background smile solo tail umamusume white_background|25563332925