Rule 34 Dev - 2010s 2018 2boys 2d 2d_(artwork) animated_skeleton bed bedroom blue_blush blue_tongue blush bottom_sans brother brother/brother brother_and_brother brothers chinese_text clothed comic digital_media_(artwork) duo ectotongue fontcest gay incest indoors interlocked_fingers intertwined_fingers intraspecies making_out male male/male male_only monochrome monster monster_boy on_bed orange_blush orange_tongue papyrus papyrus_(undertale) papysans saliva_trail sans sans_(undertale) seme_papyrus sibling_incest siblings skeleton text text_bubble top_papyrus uke_sans undead undertale undertale_(series) upper_body veah-3sin video_games yaoi|1026130