Hiding his identity as the Hero, Leo Demonhart has managed to sneak his way into Demon Queen Echidna’s forces...but he has his work cut out for him. When faced with an assassin who struggles to communicate and a warrior who doesn’t understand how to educate others, Leo knows the best solution is for them to take a page out of his long, long book. After all, he’s got a whole lot of experience under his belt, and his history stretches back further than anyone could have ever guessed...

After saving the world, the strongest hero, Leo, has nowhere else to go. His overly strong power is something that a peaceful world doesn't need. The place where he ends up working is his former enemy, the Demon Queen's Army! This is the light novel version of the Japanese major online novel prize winning work!

After saving the world, the strongest hero, Leo, has nowhere else to go. His overly strong power is something that a peaceful world doesn't need. The place where he ends up working is his former enemy, the Demon Queen's Army! This is the light novel version of the Japanese major online novel prize winning work!

After saving the world, the strongest hero, Leo, has nowhere else to go. His overly strong power is something that a peaceful world doesn't need. The place where he ends up working is his former enemy, the Demon Queen's Army! This is the light novel version of the Japanese major online novel prize winning work!

After saving the world, the strongest hero, Leo, has nowhere else to go. His overly strong power is something that a peaceful world doesn't need. The place where he ends up working is his former enemy, the Demon Queen's Army! This is the light novel version of the Japanese major online novel prize winning work!

After saving the world from the Demon Lord, the Hero, Leo, discovers that there isn’t a place for him in it anymore. The incredible strength that made him humanity’s greatest asset during the war is just a terrifying threat in times of peace, and he soon finds himself shunned from human society. But if the forces of good won’t have him, that means it’s time for him to apply elsewhere—for a job with his former enemy, the Demon Lord’s Army!

After saving the world, the strongest hero, Leo, has nowhere else to go. His overly strong power is something that a peaceful world doesn't need. The place where he ends up working is his former enemy, the Demon Queen's Army! This is the light novel version of the Japanese major online novel prize winning work!

After saving the world, the strongest hero, Leo, has nowhere else to go. His overly strong power is something that a peaceful world doesn't need. The place where he ends up working is his former enemy, the Demon Queen's Army! This is the light novel version of the Japanese major online novel prize winning work!

The Hero Is Employed by the Demon Queen...and He Still Has to Conquer a Dungeon?!Now that he’s officially joined the Demon Queen’s army, Leo is ready to take on any challenge—except, maybe, a thirty-floor dungeon set up by Shutina’s disciple and Leo’s least-favorite curse-maker, Canaan. But Shutina’s powers of persuasion (?) are hard to beat, and Leo is dragged off to face a collection of tricks and traps that might just be a little too hot to handle! As he descends the floors, though, little does he realize he’s not the only member of the Demon Heart series left in the world, and one of his siblings may be at work behind the scenes...

Leo has defended humanity for three thousand years as the world's strongest hero, but the humans have finally renounced him, and he’s quit his job for good. Now free of his past burdens, Leo plans to hand the philosopher’s stone over to the Demon Queen as a show of good faith—but little does he know it will be the cause of a terrible conflict...