I Have a Mansion in the Post-apocalyptic World - Chapter 25 - Robert’s Invitation

Luo Qiu became the boss of a ‘club’ by chance.

It was a weird club that sold strange items and with a servant girl that had 300 years of working experience. Countless people with dreams, hopes and ambitions came to the club to exchange anything precious they own for what they want. They would offer their lifespan, items, and even their soul. Every successful trade would increase Luo Qiu’s lifespan by a little.

“Tribute successful, your lifespan has increased by 99 years.”

As thus, Luo Qiu began his endless life as the club’s boss.

- Description from Novelupdates

Another entry in what you can call the Proto Harem Series: the books written before the Harem Series that take place in the same world.

It’s about a swordswoman whose student is captured, so she goes to rescue her.

Levi, a young man who spent over a thousand years in a cultivation world, awakens in a hospital only to discover that two years have passed on Earth. The world he left behind has completely changed—mysterious spiritual energy has appeared, transforming Earth into a cultivation world filled with monsters, undead cultivators, and mysterious places like floating islands.Though Levi is furious that the entity who transported him to the other world failed to stop time on Earth as promised, he must now face the new reality. In a world now filled with cultivators, interdimensional conflicts, and the presence of a cultivation leveling system, Levi struggles to adjust to his weakened human body while seeking to uncover what happened to his mysteriously missing family.