The Male Lead Is a Lower Life-Form, Born Because of the Female Lead, Unhinged, Powerful, and Sanctimonious

I can't remember which novel this trope is from: The male lead became conscious because of the female lead. To meet her again, he devoured everything in his path and cultivated like mad. When he finally got close to her, he acted refined and proper, but she saw right through him at a glance. In the end, he completely lost it.