From Overlord To Multiverse. - Chapter 19: Dungeon City.

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

To pass as an imperial concubine, one must be professional.

Actually, the profession of an imperial concubine is pretty good. The emperor will accompany you in eating and drinking, and even pay you for it. What’s not good about that?

After I was successfully captured by the Sick Princess of the Eastern Continent Empire, my free life came to an end.

“Don’t be so resistant, please be a little obedient? No matter how hard you try, the shackles, collars, and shackles are absolutely impossible to break free, so accept this little happiness early and become a cripple for me. My dear♡.”

This article contains the following elements: sickly tender, reverse push, harem, blackening. If it causes discomfort, please watch it together with your parents.

- Description from novelbuddy

After waking up in the body of the Young Master of the Luo family, he finds he has the knowledge of hundreds of games and Light Novels. However, he finds his Dantian is crippled, so he can’t practice cultivation! Luckily, he has the Upgrade system.