Very Pure and Ambiguous: The Prequel - VPAATP - Chapter V4C198 – Everything Went Smoothly

In the tenth year after the new era, the world finally came to an end. Zhang Mu truefully waited for his death, but unexpectedly found that he had returned to ten years ago. With his memory about the future, he swore that he would change the calamitous history, saving the earth from being destroyed! Walking dead, zergs, evolvers, and various mutated animals… nothing can stop him! The first step is to retrieve his identity as an era merchant , then find all the treasures he can remember to enhance himself!

- Description from Novelupdates

This legend tells the tale of the protagonist, Kuroki summoned to protect the demon king from the hero.

Kuroki, unbeknownst to him, suddenly came to another world. He was summoned by the demon king, Modes. The territory which the demon king overrules was in the midst of being destroyed because of the hero. He had no choice but to bow before Kuroki.

“Please save us, Savior Dono!”

Kuroki nodded, deciding to save the demon king due to an unexpected turn of event.

There are three realms in the multi verse; The Cosmic, the Mortal and the Nether realm.

Hal grew up in the mortal realm with no idea whatsoever of who his parents were.

His love for relics, adventure and the occasional danger would aid him in finding a genie's lamp.

Rubbing a genie's lamp should grant three wishes, but Hal is struck by lightening instead and eventually arrives in the Cosmic realm with a large book in his mind space titled; The Primordial Cosmic Grimiore, that apparently holds all knowledge for a perpetual reign.

And so Hal's journey begins in a little city called Salmon city, in the body of a 17 year old boy also named Hal but was sold into slavery by his own father.

Hal finds out who his mother (prior to reincarnation) whose bloodline now flows unmixed in his new body is....

Join Hal as he battles mortals, Dragons, phoenixes, Gods and many more together with his harem of Beauties for the complete subjugation of the three realms.

She is the legendary queen of mercenaries whose name daunts even the big shots in society. With an ancient jade pendant in her hand, she is great at almost everything, be it seeking the truth or the art of healing.