The Bankrupt Heiress's Thunderous Marriage Pact

Any Novels About a Low-Key, Down-to-Earth Billionaire?

Looking for books similar to "The Frugal Tycoon: The Top Female Donor of a Male Streamer". I want something more realistic and relatable. Stories where people casually spend tens or hundreds of millions are impossible to relate to, so they just aren't satisfying. It's way too exaggerated.