rule 34 2018 abs ambiguous gender animal genitalia animal penis anthro bed black background cetacean close up countershade torso countershading crotch shot diphallism dolphin dragon faceless male fin fish front view genital slit gradient background green skin hemipenes hybrid idoodle2draw male male only mammal marine markings multi penis multicolored skin muscular muscular male nude penis penis tip precum presenting presenting slit scalie shark signature simple background sitting slit slitfluid solo solo focus spread legs spreading vasciel aplisto white skin 2648621