Xbooru - 2010s 2018 2boys 2d 2d (artwork) animated skeleton blue blush blue eyes blue hoodie blue jacket blue tongue blush bottom sans clothed cussing digital media (artwork) drooling duplicate eye fucking eye penetration heart-shaped pupils heart eyes hooded jacket hoodie jacket male male focus male only monster penis in eye profanity sans sans (undertale) skeleton skull fucking solo focus swearing text tongue tongue out uke sans undead undertale undertale (series) unknown artist unseen male unseen male face upper body video game character video games visible breath white background yaoi