animal_genitalia animal_penis black_hair black_mane black_nose bodily_fluids brown_body brown_fur butt equine_anus equine_genitalia equine_penis eyebrows feral fur genital_fluids genitals hair inviting looking_at_viewer looking_back male mane muscular muscular_male nude outdoors outside penis presenting solo standing yiff_ai equid equine horse mammal