Xbooru - 2010s 2019 2boys 2d 2d (artwork) animated skeleton big dom big dom small sub bigger dom bigger dom smaller sub bigger male bigger penetrating bigger penetrating smaller blue blush bottom sans bottomless bottomless male brother brother/brother brother and brother brother penetrating brother brothers digital media (artwork) duo ectopenis english text fontcest from front position ganzooky gay holding object holding phone hoodie hoodie only incest larger male larger penetrating larger penetrating smaller male male/male male only male penetrated male penetrating male penetrating male monster nsfwsinningsans orange blush orange penis pants only papyrus papyrus (undertale) papysans penetration phone phone call sans sans (undertale) seme papyrus sex simple background skeleton small sub small sub big dom smaller penetrated smaller sub smaller sub bigger dom sweat talking on phone text thrusting top papyrus topless topless male uke sans undead undertale undertale (series) undertale fanfiction video game character video games white background yaoi