Xbooru - 2020s 2021 2boys 2d 2d (artwork) anal animated skeleton bigger penetrating bigger penetrating smaller black background blue blush blue tongue blush bottom on top bottom sans brother brother/brother brother and brother brother penetrating brother brothers censored censored penis clothed completely nude crying crying with eyes open duo ectopenis ectoplasm ectotongue fontcest goma dango 555 incest larger penetrating larger penetrating smaller male male only male penetrating male pov monster nude orange blush orange penis papyrus papyrus (undertale) papysans partially clothed penetrating pov penetration penetrator pov penis pixiv id 49095896 pov power bottom pussy riding riding penis sans sans (undertale) seme papyrus sex simple background skeleton smaller penetrated socks socks on solo focus tears tongue tongue out toony top papyrus trembling uke sans undead undertale undertale (series) unseen male face video games visible breath white censor bar yaoi