Xbooru - 2010s 2015 2boys anal animated skeleton bigger male bigger penetrating bigger penetrating smaller blue blush blue eye blush blushing male boots bottom sans brother brother/brother brother and brother brother penetrating brother brothers closed eyes clothed clothing crying dominant dominant male duo ectopenis fontcest from behind position fully clothed fully clothed male gloves hooded jacket hoodie incest kneel larger male larger penetrating larger penetrating smaller male male/male male only maledom malesub monster orange blush orange penis papyrus papyrus (undertale) papysans penetration penetration through clothes penis penis through clothing red boots red gloves sans sans (undertale) seme papyrus sex sex through clothes simple background skeleton smaller male smaller penetrated solid color background submissive submissive male tears top papyrus uke sans undead undertale undertale (series) unknown artist yaoi