Dxd: A demon Among Devils - Chapter 12: []:Orpheus

After his death, Bern awakens 10 years into the past as the third prince of Kailis, the enemy country.

Big Player can't reap without sowing!Have you ever seen a transmigrator forced to risk their life over copying a novel by the system?Have you ever seen a transmigrator who has to endure physical punishment by the system for quoting a famous line from their past life?I just freaking want to make some money, why's it so damn hard!System, do you dare stop messing around? I might be a fake transmigrator for all I know!……

More than ten years later, this sentence gradually spread in Elbaf Continent:

Never use magic to deal with tyrants, because you will find that he will return your spells to you thousands of times after being strengthened by countless magic specialties.

This is the story of a dragon-shaped self-propelled fort that keeps doing things in another world.

There is nothing that one magic can’t fix. If there is, then there are more. ——Izawa

- Description from novelbuddy

The strongest Demon Lord dies, and reincarnates as a human. Not only that, he because of various incidents turns into the hero’s best friend.

Follow his journey as he tries to help the hero escape his fate, and on the sideline to conquer the continent while he’s at it.