Game of the World Tree - Chapter 504

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

Kai is the hardest working warrior in his generation... and the unluckiest. In a world where most people receive magical skills, classes, or cultivation, Kai has nothing but his wits and his strength. His only choice will be to forge a new path against fate, no matter where it takes him.

Savage monsters pour endlessly from the wasteland, threatening the survival of civilization itself. They say that human strength isn't enough and only those gifted with destined powers have a chance of making a difference. Kai is hungry to fight in that war, to be someone who matters. That hunger will take him across a world stranger and more terrible than he could possibly have imagined.

I became a female character in a martial arts game I’ve played for the first time.

I know absolutely nothing about Murim, though…

An otaku with a hobby of masturbating was reincarnated as the son of a great mage.

As soon as he was born in this life, he vowed with a goal of embracing women till his death.

That said, when he became 20 years old, the Demon Lord which was sealed by his ancestors revived, and now it is his role to seal it once again.

And that demon lord is sealed in a tower dungeon that is rumored to be impossible to capture.

However, by an unexpected coincidence, he had found out that the Demon Lord is also one of him, a kindred spirit from within,

so he joined her instead and filled several traps in the tower dungeon, and thus they enjoyed a s*x spree with all the women coming over!