MTL - After Brushing Face At The Apocalypse’s Boss For 363 Days - ~ 65 | 62．61．

Yo, Hi! I’m Frank, I made a deal with a demon to pay me some money for receiving a guest for a few days every week.
I had no idea about what I have done.
On May 1st, Conan ‘the God of Death’ came to my house. I was forced to let him in and we get involved in a criminal case.
On May 8th, Bruce Wayne ‘Batman’ came to me. I was forced to follow him to fight crime.
On May 16th, Hannibal Lecter, The Silence of the Lambs, came to my home. I can only say that I really can’t stand my guests.

- Description from Novelupdates

A mysterious natural phenomenon caused the Earth to be plunged into darkness. The world turned into an endless bloody chaos and mankind is on the brink of extinction…

“Wang Cheng, we need to practice more!”

“No, I want to guarantee eight hours of sleep every day.”

…

“Wang Cheng, it’s almost nine o’clock, and you’re late.”

“Didn’t you go to work at nine o’clock? It’s still a minute away. Where’s the punch card machine?”

…

“Wang Cheng, what variety show do you want to be on?”

“Is there a fishing variety show?”

- Description from novelbuddy

Ajax was an orphan who survives a massacre along with his friends but unfortunately gets separated from them.

Fortunately, after a turn of events, he successfully gains a system which helps him increase his cultivation, but doesn't know what it is called.

But he knows one thing for sure, this system is very powerful and helpful in taking his revenge.

“Whoever you are, I am gonna find you”, Ajax mumbled himself with a disgruntled expression.

In a world where Summoning of an elemental spirit is done through a dream when they are 15 years old, Ajax with the help of a system and his summoned spirits sets out on a journey to seek revenge against the mastermind behind the massacre.