The Redemption of the Fallen Captain

Aidan Gray was the captain of one of the strongest Adventurer parties in the Adventurer world, the Eagna party. He had amassed a large amount of reputation, when at the young age of eighteen, he defeated the elusive, bloodthirsty elytra, a three-headed serpent which reeked of a vomit-like, pungent smell that could paralyze anyone who smelled it and had poisonous fang that could take life in an instant. And this was only the beginning of his success that would take the entire Adventurer world by storm.

Everything was going well for Aidan, he had fame, wealth, and power-something that every adventurer desired. Victory after victory followed him wherever he went. However, in his sixth year as an adventurer, he appeared to be nothing more than a shadow of his former self. Neglecting his comrades, as though they never existed, his training, the people's plea for help, and most importantly, taking missions, Aidan opted to indulge in alcohol until he had passed out.

When a ferocious, colossal monster attacked the Great Land of Hydra, no one, not even the strongest Adventurer parties dared to battle it, and whoever did, they never returned to see the light of day again. But one party had the audacity to face it, the Eagna party.

Although when the time came to face it, they encountered a problem: Aidan wasn't giving instructions, as he should have had, leading to a fight between him and Asteria, the vice-captain of his party. He was seen as dead weight and left behind, as Asteria took in charge of the Eagna party. But after enacting their mission, they were captured by the gates of death.

Aidan-unaware of their death-met Aoi, the goddess of time, who revealed to him the fate of his comrades, but then offered him to bring them back to life, in exchange of completing her task: Obtain the fifteen crystals of Arcane. However, they weren't located in Aidan's world, but rather, in another world: The Kazuo Universe.