Sex with his cousin is better in the mornings
We generally think that it is somehow morbid to do something, until we actually do it. Then we get used to it and this becomes… a little normal so to speak. It is true that what is forbidden stops being forbidden when we do it many times and we start looking for something else that we should not do. And that’s why, maybe that’s the only reason, for him, sex with his cousin is better in the morning. It may have something to do with the prohibition on penetrating her pussy at that time and possibly that’s why he feels that way. He’s fucking her anyway.