Xbooru - 2010s 2018 2boys 2d 2d (artwork) ambiguous fingering anal anal fingering animated skeleton armwear black armwear black bodysuit black bottomwear black topwear blue blush blue penis blush bodysuit bottom sans bottomless bottomless male bottomwear brother brother/brother brother and brother brothers clothed clothed/nude clothing duo ectopenis ectoplasm ectopussy erection fingering fingering another fingering partner fontcest gloves incest male male/male male focus male only mianpigui monster nude nude male orange blush papyrus papyrus (undertale) papysans partially clothed partially colored penetration penis pussy sans sans (undertale) scarf seme papyrus sex sitting skeleton top papyrus topwear trembling uke sans undead undertale undertale (series) vaginal video games wqw1201501125 yaoi