I Became a God in a Horror Game - Chapter 89.2: Love Welfare Institute

Bibi Dong, once the powerful Supreme Pontiff, never expected to be reborn—especially not as someone else's martial spirit. In this new life, she finds herself bound to a young soul master with great potential but little knowledge of the powerful spirit within him.As Bibi Dong guides her host, she must confront her past mistakes and figure out why she was given this second chance. Is it to correct her past, or is there something more at play?

Strength.... That's all that matters in the end.

After being abandoned by his own family, and shunned for having no mana in a world dominated by magic, ex-prince Arvell Relas Vispia was forced to live on the streets with whatever meagre money he had left.

However, fate had something else in store for Arvell.

After meeting the spirit inhabiting his amulet, Arvell gets reborn as a Nephilim.

A being that has the powers of a god.

Time, Space, Life, Death.

All submitted to the authority of a Nephilim.

Betrayed by those he once called family, Arvell swore to get revenge.

Revenge on all those that mocked him and shunned him as a 'failure.'

Revenge on those who betrayed him without a second thought.

This is a tale of how a young prince shunned by the world as a 'failure' rises and ascends to the pinnacle of strength.

The little handsome son-in-law passed through a world as waste material and the husband of a wealthy family. But because of his lacking aptitude, the wealthy family had driven him out. So he worked hard and found a more powerful family’s thighs to hold onto. Soon enough, he became the strongest son-in-law and husband in history.

In this world, it was impossible to practice martial arts. It was futile so he might as well take advantage of his wife’s thighs and maintain a comfortable and leisure lifestyle.

He’ll train his wife to become the strongest and best person in the world.

“Whoever dares to provoke me, let my wife kill you!”

- Description from Novelupdates

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates