Rule 34 Dev - 2017 5_fingers abs anal anal_sex animated anthro anthro_on_anthro antlers balls_touching cervine closed_eyes deer duo equine erection gay grey_background greyscale hip_grab horn horse klongi larger_male loop male mammal monochrome nipples nude open_mouth penetration penis sex side_view signature simple_background size_difference smaller_male stomach_bulge testicles text veins veiny_penis watermark yaoi|2897580656