Rule 34 Dev - animal_genitalia animal_penis anthro big_dom_small_sub big_penis clothing collar dewclawpaw equine equine_penis erection faceless_male feline foursome greyscale group group_sex half-erect horse horsecock male mammal monochrome muscular muscular_male penis penis_kissing sex size_difference tight_clothing yaoi zane_darkpaw|2956431032