The supporting character's harem is very normal - Chapter 61 Finally... you have appeared

The celestial celestial beings who lived for more than 100,000 years were born and reborn in a small monk in a human world.
His motto: “It’s not as good as a medicinal medicine for ten years of hard work.” “Even if you practice a copper-iron bone, it’s not enough for my soldier’s attack.”

- Description from Novelupdates

A Consort seeks prosperity.A Shepherd cloaked in yellow wages war.A Prosthesis-wielder cries out for retribution.Shadows tremble in the depths, encompassed worlds obscuring the many dangerous secrets of history. Might they be unraveled, all ways of life would be threatened. But to climb higher requires risks, to seek the light requires a Gambit of Lifetimes.Only when one determines themselves capable of risking it all, can all prosper.

A great demon king who came from another world to conquer Earth. To save the Earth, Li Luyou could only first take care of this great demon king… a little girl proclaiming herself Her Imperial Princess.

- Description from Novelupdates

In the city of Graheel, a small antique shop sits quietly mixed in with all the other shops. Its unassuming appearance is easily overlooked by many. However, this store and its owner has a terrible secret. A devil lives in that building. The owner of the store, John Li, an enigmatic figure whose origins and intentions are unknown. The desperate from around the world, often unknowingly, come to him in search of salvation.A red witch thinks the owner is an ancient creature, a white fox calls him a wizard of eld, a warrior believes him to be a spirit, and a holy woman declares him a god. This mysterious individual and his customers would stand at the center of a strange series of events. From the store owner John's perspective, he has no idea what's going on. He really was just an unlucky dude that got caught up in some crazy stuff.