Samuel was but naked, bumping belling with someone he had just met! He tried shaking her up but to no avail. She was still passed out, and he began to get flashbacks of everything that had happened the previous night.
He couldn't believe that he had gone wild and Kate, who seemed normal, was a freak in bed. People often say older women have much experience, but that was not the case for Kate. She was a little rough around the edges, but Samuel had managed to get her out of her shell.
It could also be that both were intoxicated, which led to these events to unfold. He was lying on his back, just staring at the ceiling. He didn't want it to be awkward between them, so he started thinking of a plan to get out of the situation and didn't mention it.