Zatch Bell Movie 1: 101st Devil

While the battle to determine the next king of the demon realm has often been fraught, the rules were always clear: 100 demon children partnered with 100 humans would challenge each other, using 100 magical books. What none of them knew was that there was a 101st magical book, powerful enough to stop any of the others. Gash and Kiyomaro must begin a journey that will take them into the demon realm to confront the mysteries of Gash's past. But will they escape in time to help their friends in a battle with a seemingly unstoppable enemy.
While the battle to determine the next king of the demon realm has often been fraught, the rules were always clear: 100 demon children partnered with 100 humans would challenge each other, using 100 magical books. What none of them knew was that there was a 101st magical book, powerful enough to stop any of the others. Gash and Kiyomaro must begin a journey that will take them into the demon realm to confront the mysteries of Gash's past. But will they escape in time to help their friends in a battle with a seemingly unstoppable enemy.

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