FURVERT!

abs anatomically_correct anatomically_correct_genitalia anatomically_correct_penis anatomy animal_genitalia animal_penis anthro anus backsack balls biological_illustration bone butt close-up equid equine equine_genitalia equine_penis erection flaccid genitals horse how-to male mammal model_sheet muscular muscular_anthro muscular_male nude penis sheath simple_background skeleton solo species_sheet technical_illustration trogan vein white_background