gelbooruhttps://xbooru.com/index.php?page=atom&tags=2017 2d 2d (artwork) animated skeleton blue blush blue tongue blush bottom sans crying crying with eyes open from behind gaster gaster (undertale) grabbing pillow male male penetrating monster penetration sans sans (undertale) sanster seme gaster sex sinfulsanspar skeleton smiling tears tongue tongue out top gaster uke sans undead undertale undertale (series) video games yaoi2024-06-05T14:25:04Zgelbooru