Rule 34 Dev - anthro balls big_balls big_penis blush blush_lines bodily_fluids bouncing_balls breath clothing erection footwear foreskin fur genitals glans gloves half-closed_eyes handwear humanoid_genitalia humanoid_penis lying male markings masturbation muscular muscular_anthro muscular_male narrowed_eyes on_back open_mouth panting penetration penile penile_masturbation penile_penetration penis pink_glans red_body red_fur shoes simple_background solo spiked_gloves spikes spread_legs spreading sweat sweatdrop thrusting white_background white_clothing white_footwear white_gloves white_handwear white_markings white_penis white_shoes hpyononyo sega sonic_the_hedgehog_(series) knuckles_the_echidna echidna mammal monotreme 2d_animation animated digital_drawing_(artwork) digital_media_(artwork) frame_by_frame hi_res short_playtime watermark|18903135930