History's Strongest Live-In Son-in-Law

(Completed) After transmigrating to another world, he became the pretty boy son-in-law of a wealthy family, but they threw him out for being useless. So he worked hard and found an even more powerful and beautiful heiress from a wealthy family to marry into. There's no way I'm learning martial arts, not in this lifetime! I'll train my wife to become the greatest martial artist under heaven. Anyone who dares mess with me will get beaten to death by my wife!