Xbooru - 2010s 2018 2boys animated skeleton big dom big dom small sub bigger dom bigger dom smaller sub bigger penetrating bigger penetrating smaller blue eye bottom sans bound arms bound wrists brother brother and brother brothers clothed clothed/nude crying crying with eyes open duo ectopenis fontcest glowing eye heart incest larger penetrating larger penetrating smaller legs on another's shoulders legs on shoulders legs over partner's shoulders legs over shoulders lowest-of-dirt lowest of dirt male male only male penetrating monster mouth gag naked nude papyrus papyrus (undertale) papysans penetration penis sans sans (undertale) seme papyrus skeleton small sub small sub big dom smaller penetrated smaller sub smaller sub bigger dom sweat tears tied arms tied up tied wrists top papyrus uke sans undead undertale undertale (series) unseen male face