Strike Back, Proud Goddess! - Chapter 2 - Visitors

The strongest Demon Lord dies, and reincarnates as a human. Not only that, he because of various incidents turns into the hero’s best friend.

Follow his journey as he tries to help the hero escape his fate, and on the sideline to conquer the continent while he’s at it.

Hiding in the Cold Palace and eventually becoming a Boss of Sorts. Li Mu was transported to a fantastical world and became a measly eunuch of the State of Xia. Despite having initially thought that his life would be a miserable one, he had unexpectedly acquired a check-in system.

Luo Zheng is at the bottom of the Luo Clan hierarchy, despite his family being the founders of a power refining technique that could instantly defeat any opponent.

One night, enraged by unfair treatment from a family steward, Luo Zheng burns the family records. In doing so, the hidden magic in the book engulfs him and Luo Zheng becomes a new skilled fighter. Fleeing his home and despicable clan, Luo Zheng must learn to harness his powers to rescue his younger sister while his own cousins are on his pursuit.

- Description from Novelupdates

He died in his first life, as an ordinary human inside an ordinary planet.

In his second life, he swore to live a life of supreme power, and so he did. He reached the apex and exterminated his enemies to oblivion.

Dying, he was reincarnated in a world which could use Chakra. He became The Overlord Of Every Being, Ruler Of 6 Universe.

Unfortunately, he died. Using a mysterious method, he was reincarnated once again inside the world of Tales of Demons and Gods.