Crown of Thorns - Chapter 71

Every human on Earth was transformed into a summoned monster and was summoned to another world.

System, “You have a sickness. Moreover, you’ll have one in every world.”

Hao Ritian, “…”

System, “What’s wrong? Is there a problem?”

Hao Ritian smiled, “No, there’s no problem. I was just a bit excited.”

System, “…”

That smile intensified the system’s feeling of ominous foreboding. It has had this premonition since it learned the name of its host. Now it only prays that this is all its imagination!

Ps: Protagonist shou 1v1, the gong is always the same person.

- Description from Novelupdates

When we met for the first time in our first year of high school, he saw my contempt, but silently continued to clean;

This is a story of a man named Kim Sae-Jin, who one day, inexplicably wakes up as a Monster. Follow him and his perilous journey to get his life back as a Human, all the while growing even more versatile as a Monster in the process. This should be… complicated, somewhat.