rule 34 2023 animal genitalia animal penis anus ass avian balls beak big anus big perineum black anus black balls black pawpads black penis black perineum brown eyes digital media artwork digitigrade equine penis feathers feral fur genitals grey background gryphon half erect hi res looking back male mythological avian mythology pawpads penis perineum presenting quadruped raised leg red body red feathers red fur simple background solo teavern tongue tongue out yellow beak 7242109