Стыд или сожаление за то, что произошло вчера с моей сводной сестрой

I lived with him daily and practically 24 hours a day. However, everything that happened the night before left her silent and strange after what happened. He didn't know what to do, he didn't know if she had enjoyed it, but he was possibly embarrassed or sorry for what had happened between the two of them the night before. Then when he went to bed, she asked to lie down with him again, which was enough to rekindle something that would be inevitable again...