abs anal anal_penetration animal_genitalia animal_penis anthro balls basement biceps big_muscles black_nose broad_shoulders canine_genitalia canine_penis digitigrade duo genitals knot knot_root knotted knotting looking_pleasured male male/male muscular muscular_male pecs penetration penis sheath size_difference wolfgrinn canid canine canis mammal were werecanid werecanine werewolf wolf