Xbooru - 2020s 2023 2boys animated skeleton bedroom big dom big dom small sub bigger dom bigger dom smaller sub bigger male blue hoodie blue jacket boots bottom sans bottomless bottomless male brother brother/brother brother and brother brothers duo ectopenis ectoplasm fellatio fellatio pov fontcest hooded jacket hoodie incest indoors jacket japanese text larger male licking licking balls licking penis licking testicles male male/male male only male penetrating male pov monster papyrus papyrus (undertale) papysans partially clothed partially clothed male penis pov red boots red penis s2ames2 sans sans (undertale) seme papyrus sex skeleton small sub small sub big dom smaller sub smaller sub bigger dom text top papyrus trembling trembling legs uke sans undead undertale undertale (series) unseen male face yaoi