Not like shield hero, not like aruefuerte, and not like most of the stuff you've seen or read before. Think at the likes of Goblin Slayer.
Once again this story is dark and chapter 14 has confirmed that for me for the third time while reading this story.
It's gruesome as the story goes on about a "hero" a human who achieved great success and after losing all his allies, love, family, and comrades reaches the enemy of humanity, humanity being the basic human laws, right, and privlages. He arrives battered and broken at the demon kings room to wage war by himself. Though acknowledged this hero is only able to push the demon king to use his true power for a mere few seconds before his soul is devoured...
The hero awakens in the body of a young demon that shares blood with the one who slew him, half demon and half human. He will see his comrades again, his loved ones again, and the human alliance again but now from the other side. He will see those that killed his loved ones as allies in the demon kings army. His hatred will grow and shrink with the new people he meets.
His beliefs of what horrors await if you are captured by the demon kings army are shown. He will have to fight those he once believed allies to finish his believed mission. Now we just keep reading and wait as the story plays out to see what he does. Can he really achieve it? Can another hero another human do what he couldn't, can he make peace or finish this war😕
Edit (Axed): Sad it got axed. It's not a Manga for shonen kids like BlackFlame. It's definitely an adult Manga that is dark, similar to berserk. It had MUCH potential but maybe the Japanese market didn't like it much. Since this is the authors only work we may not see another story and we can only hope for a novel continuation to see where the story was going as that also doesn't exist. Same goes for the artist whose only work is this Manga.
It's a bit sad for that got axes and is still sorta worth the read with the knowledge that the axed ending sucks.
Also look at the user ratings. People enjoyed it.