rule 34 anthro anus ass backsack balls big butt bodily fluids devourer razor koopa digital media artwork dragon genitals goo creature goo dragon goo dripping horn humanoid genitalia humanoid penis larger male looking at viewer looking back male muscular muscular anthro muscular legs muscular male muscular thighs nude penile penis perineum purple body raised tail rear view simple background size difference slime solo spikes spikes anatomy spread butt spread legs spreading tail thick thighs zawn 8275661