Rule 34 Dev - 2019 2boys 2d 3:2 alternate_universe animated animated_skeleton anterior_nasal_aperture ass bandana bite biting_lip biting_own_lip blue_clothing blue_gloves blue_handwear blush bone brother brothers closed_eyes clothed clothing duo fully_clothed gif gloves green_background handwear humanoid implied_incest incest kerchief lizheru lizherubones looking_at_another loop male male_only motion_lines neckerchief orange_clothing papyrus sans self_bite shaking_ass shaking_butt short_playtime sibling signature simple_background skeleton teasing teeth twerking undead underswap underswap_papyrus underswap_sans undertale video_games|5732156504