Xbooru - 1boy 2010s 2016 2d 2d (artwork) animated skeleton bad id bad tumblr id blue tentacles blue tongue bottom sans bound bound arms bound legs bound wrists completely naked completely nude digital media (artwork) ectotongue legs held open male male only monster naked noxiousaberration nude one eye closed sans sans (undertale) simple background skeleton solo tentacle tentacle on male tentacle sex tentacles around arms tentacles around legs tentacles around wrists tentacles on male tongue tongue out uke sans undead undertale undertale (series) video games