Conquest Of The Fallen: Dark Dominions - Chapter 239 Damnamenaeus

Four years ago, after a night of drunkenness, she had a relationship with a stranger and fled in panic upon waking up. Four years later, she returns with a soft, cute little bun by her side.“Bad uncle, you're not allowed to bully my mommy!”The man looked at the little bun, who was not even tall enough to reach his waist, and gave a charming smile. “Shouldn't you ask your mommy why you look exactly like me?”

“A cheat system? Do you take me for a fool? Nowadays, where can you find such a good thing falling into your lap? Scram from my head. Is this is new kind of fraud? Or is this a murderer training system of aliens that contains the ability of hypnotism?”

“No, I am the chaos that whispers from nothingness, the nightmare of all living beings in the Southern Ten Stars, the successor of the unparalleled God and… your elder sister.”

“…I only have a younger sister, I don’t have an elder sister!”

“No, you have one. I am an illegitimate daughter. It’s just that your dad didn’t inform you.”

- Description from Novelupdates

Shiloh is an Dominant Omega, in a world where he lives Dominant Omega and Dominant Alpha only born among the elite. So when his father sold him to some 'Madam', everyone used him. Shiloh got a lot of bad treatment until he meets Gruvv, a Dominant Alpha. Gruvv himself has a problem, he can't smell pheromones because of his depression. He was never in a RUT again and his family was constantly looking for ways to get him to smell pheromones again. In the side, Gruvv is the heir to the DHURUDATTA family, a mafia family that also made Shiloh's father run away because of his debts.