NTR: Choice Based System - Chapter 1: system has activated ( The Beginning arc)

A cauldron, a secret forging method, and his blood created an ultimate weapon. The youngest Sword Crafting Master on Earth had been reborn from another world. With the Nine Yang Divine Furnace and a scroll of Divine Equipment, he was like a fish in water, standing at the pinnacle of the martial way. There were tens of thousands of clans, billions of cities, and countless experts. He was the master of ups and downs!

While the demons were rising, mankind was about to become extinct. Six temples rose and protected the last territory of mankind.

What happens when a fanfic author with a habit of lying and scheming suddenly finds himself as a self insert during Duelist Kingdom? What happens when you have Yugi, Joey, Kaiba, and the rest encounter someone who knows all about every major player in their saga... and sees no problem with abusing said knowledge? Chaos, dear reader. Sweet, sweet chaos

Ruan Tian is a cat which gained sentience, and is infatuated with the goddess who once saved him. During the college class reunion, Ruan Tian once again confessed to her, but she openly proclaimed that she would only marry Qin Li and no one else.

Qin Li was Ruan Tian’s number one enemy and love rival, and he was born to put Ruan Tian down for a hundred years!

Ruan Tian looked at him furiously. “Let’s battle! Only one of us can remain!”

Qin Li: ▼_▼ Shall we get on the bed?

- Description from Novelupdates