The Vault of Sin: A Secret Society Billionaire Reverse Harem Romance

A secret society runs the city from a vault beneath its streets—and your sister walked in chasing truth… then vanished.

Now an investigative journalist follows her last five words into the dark, only to find The Vault waiting with a contract already written and three billionaire kings already watching.

Dorian is charm sharpened into a weapon. Knox is silence with fists. Silas is cold, brilliant control. They don’t offer help—they offer terms: survive their tests, learn the rules, and earn fragments of the truth. Refuse, and the Vault erases you like you never existed.

Every corridor shifts. Every door is a trap. Every lesson blurs the line between danger and desire. And the deeper she digs, the clearer it becomes: her sister didn’t just uncover a conspiracy—she triggered it.

To get her back, she must infiltrate an empire of secrets, outplay men who own everything, and decide what she’s willing to sacrifice when love becomes leverage… and sin becomes the price of freedom.

The Vault has a motto: once you see, you belong.