Rudy was tired as he had used a little too much of his power in fighting Pieru, and he had got no rest ever since then. He felt comfortable in the company of Elena and Rebecca and that made him fall asleep on her shoulder.
He wouldn't have woken up for a few hours if Rebecca hadn't woken him up, but that was necessary. Even if Rebecca had stayed the night at Elena parent's house, she would still have to wake Rudy up as she couldn't leave him in the car.
After teleporting back to his house, Rudy was still asleep, but he was no longer tired. He had gotten an adequate amount of rest to go on for a few days without sleeping.
However, he was surprised when Rebecca asked him to wait for her in his room.
As soon as Rebecca told him that, a sudden thought crossed his mind about what was going to happen, but he shook his head and dismissed it. He couldn't imagine Rebecca suddenly taking an aggressive turn in their relationship.
