rule 34 2019 all fours ambiguous gender ambiguous penetrated anal anal sex animal mask anthro ass avian beak beak mask bird blush cauldron clothing corvid corvus genus crow digital media artwork gy style duo feathers feet from behind position gloves halloween handwear headgear hi res holidays looking at viewer male male only male penetrating mask nipples nude paws penetration penis plague doctor science sex simple background testicles tigertooth 3454941