Dark Old Demon

Roy's life was nothing special. The only thing commendable was the last few moments when he saved a mother and her child from a drunk driver.
...
It's really an egg! Damn it, what kind of monster have I become? Did I fall into Hell instead of making it to Heaven??
Join Roy as he ventures through various worlds with the Custom Made Demon King System—a system that allows Roy to draw anything he can imagine and create it through exchanging souls!

Custom Made Demon King

High-rank demon?! He's actually a high-rank demon?!

Roy had a vague guess before. Even a middle-rank demon could not have offset his Bloodlust effect with a single spell. But hearing for himself the other party acknowledging that he was a high-rank demon still left Roy in amazement.

Damn it, what bad luck. I didn't expect a high-rank demon to summon a demon. If I had known, I wouldn't have stepped into the magic formation and responded to the summon…

Roy was very clear of how high-level demons viewed the low-level ones. There were only two attitudes—kill or enslave. There were no other options. Roy did not have to look at the demon contract to know that it was an enslavement contract.

Elite Demon