His thrusts were slow and methodical as he gauged your reactions. He had filled your need of needing to have him inside you, but now a new need was starting to rise. That knot in your middle was getting bigger and it needed more than just slow thrusts.
Luckily, you didn’t have to tell Mettaton because he was starting to feel it; his thrusts were starting to get faster and rougher as his breathing hitched, his fingers digging into the skin at your waist.