He must be really bored, bored enough to start looking for things to do for himself.
After sitting for a while, Nathaniel York got up and went to the bathroom to take a shower. When he came out, he didn't put on clothes and went to bed. In a few moves, he took off Matilda Jenkins' clothes.
He was so tired; he needed to find some comfort for himself.
Matilda's body was soft, just like her personality, soft and gentle. She was quite adorable when unconscious, at least he didn't have to be bothered by her anymore.
Nathaniel couldn't sleep after lying down. He was tired all night, holding the soft body, but he didn't make any extra moves. On the contrary, he felt comfortable with the physical instinctual reaction and the desire.
This kind of comfort probably couldn't be explained to others because he himself didn't know how to describe it, and he probably wouldn't tell anyone.