At last, Hajime has conquered all seven labyrinths and found a way home. But a massive army of apostles awaits him outside the Frost Caverns-led by Fried, supreme commander of the demon army. Fried has an invitation for Hajime, one he can't refuse: come to the Demon Lord's castle, or lose his old classmates...and Myu. Left with no choice, Hajime surrenders. Little does he know, terrible secrets await him in the heart of the demon empire, and the revelation of Ehit's true plan may destroy him once and for all.