Swordsman Returns from Another World

I have been thrown into countless different worlds, and in order to survive, I had to take the path of a villain.
And now I have a new identity, the evil spirit of the Tower of Babel, the doctor of Rhodes Island... the harem king of Terra.
Use the powers that belong to the other world to change this land full of tragedy.
I used to be a quality inspector at Type-Moon Heavy Industries, and I conquered the world in the name of Lance, and that power came with me.
"Believe me, I blame this world for turning into a harem king!"
"I want to save this damn world! And redeem those regrets!"
"Come, see me as a player, as the fourth calamity!"
[Wu Geng War God, quality and quantity guaranteed, large quantity and fullness]