Rule 34 Dev - 2016 5_fingers abs anthro anthro_on_anthro balls biceps big_balls biped canine claws clenched_teeth duo erection fasttrack37d fellatio furry german_shepherd grey_background greyscale highres huge_balls humanoid_hands hyper hyper_penis interspecies kangaroo larger_male lifting male male_only male_penetrating mammal marsupial maurick monochrome muscular muscular_male nipples nude oral oral_penetration pecs penetration penis penis_grab penis_size_difference scott_(fasttrack37d) sex simple_background size_difference smaller_male snout standing teeth thick_penis upside-down watermark yaoi|2471743592