Rule 34 Dev - 1boy 2015 2d anthro anthro_male anthro_only asriel_dreemurr balls black_sclera boss_monster caprine electrixocket erection fur furry furry_male furry_only goat horn humanoid humanoid_male humanoid_only humanoid_penis male male_only mammal mammal_humanoid masturbation monster pecs penis precum presenting presenting_penis simple_background solo speech_bubble uncut undertale undertale_(series) video_games|2133353096