I am that male friend in the harem story - Chapter 1: Hardcore Beginning

Eldraus was once a normal world , peaceful, beautiful and full of life, much like Earth.But everything changed when the Beast Mutation began.Animals started turning into terrifying monsters larger, stronger, and unnaturally violent. Kingdoms fell. Cities burned. Humanity was pushed to the edge of extinction.Then came the System, a mysterious power that awakened within humans, granting them abilities to fight back. Over time, the system became a part of everyday life. Every person now awakens with a System, ranked from the weakest gray to the legendary black and above.This is a world where strength rules, and the weak are left behind.Kaelen Maglor, son of a noble, awakens with a rare black support system. People mock him, expecting him to be a healer. But Kaelen has no intention of following their path. He chooses to walk his own.With danger rising and powerful enemies lurking, Kaelen enters a deadly academy that trains the next generation of fighters. There, he will uncover secrets, face deadly trials, and learn that the system that grants power... might also be hiding a terrifying truth.In a world where monsters roam and only the strong survive, Kaelen must prove that even support can become unstoppable.

Liola—the best assassin in his world—has vowed to kill no more. He was being chased by an assassination organization when he accidentally dropped into a parallel universe: through a dimensional gate and into poor teenager Kaiser’s apartment. Instead of going to the government shelter for lost dimensional travelers, Liola and Kaiser wind up going to school together.

Liola has been trying his best to live the life of an ordinary person, but after certain things happen one after the other, he begins to realize that being an ordinary person could be harder than being an assassin.

In the Province of the Nine Skies, far above the heavens, there exists Nine Galaxies of Astral Rivers made up of countless constellations interwoven together.

A back-to-basics(?) monster evolution novel.