Having children earns benefit, start competing for dominance in the world by marrying a wife - Chapter 558 - 337: Disciple Thanks Master for His Fulfillment_1

Yo, Hi! I’m Frank, I made a deal with a demon to pay me some money for receiving a guest for a few days every week.
I had no idea about what I have done.
On May 1st, Conan ‘the God of Death’ came to my house. I was forced to let him in and we get involved in a criminal case.
On May 8th, Bruce Wayne ‘Batman’ came to me. I was forced to follow him to fight crime.
On May 16th, Hannibal Lecter, The Silence of the Lambs, came to my home. I can only say that I really can’t stand my guests.

- Description from Novelupdates

An Individual from Earth finds themselves in the Shinobi World, equipped with a Scientific System. From that moment, he delved into scientific research far ahead of its time.

.In order to make up for the regrets of his past life, Ye Fan transfers to the high school Ning Xi attends after his rebirth, finding the beautiful figure from his memory. In his memories, Ning Xi lay on the operating table, using her last breath to say, “Brother, I... I like you...” In this life, watch how Ye Fan conquers the heart of the soft and genius school beauty step by step. ...

Zhangsun Zijun and Yi Xichen are the protagonists of the novel “Record of Nine Thousand Vicissitudes.” One is solid and reserved; the other is free-spirited and uninhibited. As fellow disciples under the same master who grew up together, the two have a deep friendship that was strengthened by their numerous life and death adventures together.

However, in a popular yaoi fanfiction, the personalities of these two characters is completely OOC. Zhangsun Zijun turned into an insanely jealous, insatiable s*x addict madly in love with his wife Yi Xichen. Yi Xichen turned into a sweet, delicate little angel. Their daily life was full of kinky bedroom activities…

Suddenly, the Zhangsun Zijun character from the fanfiction was transported into the world of the original novel.

- Description from Novelupdates