The invasion of a malevolent deity has brought the spirit world to its knees! Rista falls unconscious amid the turmoil, and when she next opens her eyes, she finds herself in a distorted version of Gaeabrande. Here, humans and demons have joined forces against a much greater foe, forging alliances as bizarre as Rosalie Roseguard and Chaos Machina! Nothing makes sense anymore, so why not double down on the madness? In order to save the spirit world, Seiya is summoned once again, and this time, his base of operations will be...the underworld!

There's no such thing as too much preparation! The fate of the S-ranked world Gaeabrande rests with the novice goddess Ristarte. As she thumbs through the piles of duller-than-dull résumés for potential Heroes to summon, she hits the jackpot with Seiya Ryuuguuin, whose stats are so high for a level-1 Hero that he's practically cheating! (He's also pretty easy on the eyes.) But there's a catch. Seiya is cautious to a fault. If he goes to a weapons and armor shop, he asks for three sets of armor: one to wear, a spare, and a spare for the spare. Just in case. He always buys ridiculous amounts of supplies, trains like he's racing to max level, and won't hesitate to use his strongest skills even on a simple slime. With a Hero like Seiya on the job, which will run out first-the Demon Lord's forces or Ristarte's sanity...? The tale of the overpowered yet overly cautious Hero and the goddess who can't decide if she wants to kiss him or smack him begins!

I’M SORRY. Feeling ill-prepared for the looming battle against his former pupil, Seiya returns to the underworld to acquire some new skills. But every boon gained from this realm comes at a cost—Rista’s dignity. First, his group hones their stealth abilities by learning invisibility magic. Then, Seiya ventures to the Infinite Corridor to harness the powers of darkness! They’ll need more than a couple new tricks to defeat Mash, the Dragon Lord, though. To gain an edge in the fight to come, they will have to peer into the past and learn the tragic origins of Warped Gaeabrande…

Lista, a Goddess from the God's realm, has a huge task to accomplish. She must save the world Geabrande (with a S-rank difficulty salvation) from evil threats. To perform this task, she summons a hero from Planet Earth called Ryuguuin Seiya. This hero is exceptional and fully capable, but has one major problem: he is unbelievably cautious.

Ristarte summons a hero who excels in every area to assist her. He's everything she expected him to be except for one, tiny thing: this anxious hero can't do anything unless he's absolutely sure nothing can go wrong! The manga adaptation of the break-out hit is finally here!

WHAT COULD HAVE BEEN...Beast Emperor Grandleon, Machine Emperor Oxerio, and Vengeful EmpressCelemonic have all been defeated by the cautious Hero. As Seiya, Rista, Kiriko, andJonde travel to the west to face the Death Emperor, the last of the Demon Lord'sgenerals, though, they are wholly unprepared for what they fifind: a town full ofhappy people, all living peaceful lives. And why wouldn't they be? Accordingto them, the Demon Lord was defeated over a year ago by none other thanSeiya Ryuuguuin himself! As the party's heads flflood with questions, a familiarsilhouette appears on the horizon...

The invasion of a malevolent deity has brought the spirit world to its knees! Rista falls unconscious amid the turmoil, and when she next opens her eyes, she finds herself in a distorted version of Gaeabrande. Here, humans and demons have joined forces against a much greater foe, forging alliances as bizarre as Rosalie Roseguard and Chaos Machina! Nothing makes sense anymore, so why not double down on the madness? In order to save the spirit world, Seiya is summoned once again, and this time, his base of operations will be...the underworld!