MTL - I Don’t Want To Go Against The Sky - Chapter 54 That's right.

When he stayed at her home and one night, he took her body in a drunken stupor. From then on, he had been a constant fixture in her life. How adamant he was in forcing a marriage was how adamant she demanded for a divorce. “I’m not staying married to you! I’m not staying married to you! I’m not staying married to you!” After she repeated such an important proclamation three times, he finally tossed her the divorce paper. She thought she had finally escaped him alas… After the divorce, he still snuck into her room every night… Finally losing her patience, she yelled, “We are already divorced!” He glanced at her and set down the divorce paper before her. On it, it was written clearly: After the divorce, the car is hers, the house is hers, the company is hers, their child is hers, he… is also hers?

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!

The MC entered the body of the An family eldest son, An Ziran, an arrogant 16 years old boy who weighed 78 kg (~171-172 lbs), who only knew how to eat, play and sleep. Seeing his current body, An Ziran decided his first priority was to LOSE WEIGHT!