\— Now, let's kill the girl and save the world! The world has been shattered. As a result of the most dreadful of diseases that afflicts only girls —- the 《Labyrinth Disease》. That's why the students are taking lessons. Lessons for the purpose of killing the girl. Learning magic, figuring out the map of the labyrinth, forming teams, and studying the weakness of the girl...... The time limit is 6 hours. If the girl isn't killed within that time, then the world gets destroyed. "I have no interest in the world at all so please spare me. Frankly, it's really suffocating." Together with the one who said these words, the most horrible protagonist in history, enter the world of whizzing magic and surging youth. A school fantasy in labyrinth raiding, begins here!

「なんせ俺らは世界を救った仲間だろ?ほら手を取れよ。友達になって下さいって言え」「うぜぇ~」朝日桃花を殺し、世界を救ってから1か月。迷宮から生還した真之介たちは、本人たちの仲の悪さとは裏腹に、いつしか「英雄チーム」と呼ばれる存在になっていた。だが、彼らの本拠たる吉祥寺で“迷宮病”が発生する。発症者は、真之介のよく知る「あの少女」!?しかも、関西から少女殺害のため、精鋭魔術師「勇者チーム」が現れて…。一瞬刹那で魔法を使う、少年少女迷宮突破型ファンタジー!絶望に満ちた迷宮の果てに、真之介を待つのは―!?