Xbooru - 2010s 2016 2boys 2d 2d (artwork) animated skeleton big dom big dom small sub bigger dom bigger dom smaller sub bigger male bottom sans digital media (artwork) hair hoodie humanoid humanoid robot larger male male male/male male only maledom mettasans mettaton mettaton ex monster penis robot robot boy robot humanoid robotic penis sans sans (undertale) seme mettaton skeleton small sub small sub big dom smaller sub smaller sub bigger dom top mettaton uke sans undead undertale undertale (series) unknown artist video game character video games wearing others clothes yaoi