Satan has transformed himself into a gigantic Gehenna Gate, and is attempting to absorb all of Assiah by expanding a rip in the dimension. Rin and Yukio, joined by Shura and Angel, attack the gate, but it's an uphill battle against Satan's overwhelming power. Meanwhile, at the school, the exorcists are in a desperate situation, as a myriad of demons attack. Just then, Suguro proposes a strategy for a comeback! But will it work? Rousing themselves into action one last time, Rin and Yukio head toward the gate. To protect their beloved friends, and this world!