My Shadow Monarch's System - Chapter 22: The Imperial Arms.

Zhou Yu, a reclusive otaku, who did not like to go out of his house, was one day forced out of his house by a series of unexpected events.

- Description from Novelupdates

Beings that create and control monsters and demons, beings that build and reign over malicious labyrinths, the chosen individuals to possess an overwhelming Unique Skill… They are the Demon Lords.

While the demons were rising, mankind was about to become extinct. Six temples rose and protected the last territory of mankind.

A young boy joins the temple as a knight to save his mother. During his journey full of miracles and tricks in the world where temples and demons are antagonistic to each other, will he be able to ascend to the strongest knight and inherit the sealed divine throne?

- Description from novelupdates

Holo’s life was once a series of relentless hardships—bullies at school, abusive parents, and heartbreak at the hands of those he trusted. After a failed suicide attempt, a mysterious man offers him a deal: help rehabilitate four psychopathic girls, and in return, earn ten million dollars. Desperate and naive, Holo accepts, not realizing the chaos and danger awaiting him.Each girl comes with her own dark tendencies—Trixie, a violent and feral girl who acts on impulse; Scarlet, a master manipulator who delights in breaking people down; Felicia, a dangerously seductive woman battling a sex addiction; and Eleanor, a cold, calculating girl with a desire to watch the world burn. As Holo works to bring out their humanity, the girls become obsessively devoted to him, their love transforming into something darker.