FURVERT!

4:3 all_fours anal anal_penetration anthro anthro_on_anthro anthro_penetrated anthro_penetrating anthro_penetrating_anthro balls barefoot duo echidna eulipotyphlan feet genitals hedgehog hi_res knuckles_the_echidna krazyelf male male/male male_penetrated male_penetrating male_penetrating_male mammal monochrome monotreme nude penetration penis sega sex sonic_the_hedgehog sonic_the_hedgehog_(series)