Imagine being summoned to another world to be the hero, beat the Demon King, and live an adventure...only to be forced to return to modern-day Japan. That’s what happened to Hizaki Shio. Those exploits seem like forever ago—he is in high school now—even though it’s only been three years. But just as Hizaki has settled back into reality, he’s suddenly summoned again and this time to stop the Secret Society, Helheim! However, Shio has a slightly cringey secret... He founded Helheim himself, during an embarrassing phase when he went around calling himself the Corpse King. It’s physically painful to remember. So who could be using Helheim’s name in his place, and how did it become so powerful? It’s time to confront the marks he left behind. First stop: the Steel City of Gaghiel to rescue a noble heiress!Suggested 15+

Imagine being summoned to another world to be the hero, beat the Demon King, and live an adventure...only to be forced to return to modern-day Japan. That’s what happened to Hizaki Shio. Those exploits seem like forever ago—he is in high school now—even though it’s only been three years. But just as Hizaki has settled back into reality, he’s suddenly summoned again and this time to stop the Secret Society, Helheim! However, Shio has a slightly cringey secret... He founded Helheim himself, during an embarrassing phase when he went around calling himself the Corpse King. It’s physically painful to remember. So who could be using Helheim’s name in his place, and how did it become so powerful? It’s time to confront the marks he left behind. First stop: the Steel City of Gaghiel to rescue a noble heiress!

Secret Society Helheim sets off to raise money and procure materials in the land of desires—the Sleepless City of Shehem—where they are reunited with Hræsvelgr of the Eight Precepts and guardian of the Divine Tree Yugel. However, she hasn’t forgiven the Corpse King for vanishing one hundred and eighty years ago, and the reunion quickly turns violent. Meanwhile, the residents of Shehem are plagued by dreams of two massive serpents. The Corpse King accepts a request from a longtime ally to unravel the mystery, but it isn’t long before he finds himself wrapped up in the conspiracies writhing beneath the Sleepless City. And as the chaos grows, powerful figures are converging: the Lv8 Explorer Crimson Bloom, the demon knight Furcas, and even humanity’s strongest gathering, the Hall of Many Kings...

The proud greater demon, Marquis Marchosias, trembles with rage. The very concept of heroes has become a farce—entertainment to be consumed and discarded. It was with bravery and conviction that a true hero once cut down the mighty Demon King. To belittle the Hero is akin to insulting every demon who fell before his blade. So as news of yet more “heroes” appearing reaches his ears, Marchosias ventures forth with a question: Are they the real deal? Meanwhile, Helheim, after saving the Sleepless City and taking in a Cait Sidhe, sets its sights on restoring the Corpse King’s lost power and heads for the Empire’s Lv9 Hidden Land, the Heavenly Prison. Their timing coincides with Hyouka and the other heroes, who have come with an escort of color explorers including the Empire’s own Black Valor, Artel Nanoire. It is here—in a hidden land shrouded in mystery and fraught with danger—that their convictions shall collide.