The council's rampage sends quakes through the demon realm, and the demon Chaos is called forth through a giant magic circle. That commander of all heroic spirits flails madly, seeking to claim Basara, Mio, and Leohart's lives. Do they even stand a chance of victory with this supreme being before them?! Meanwhile, Maria, Yuki, and the others put a final end to their own personal battle. "Believe in me... once more." The ultimate sibling combo risks their lives to face the disaster striking all of the demon realm!