On one rainy day, an Adapter attacks the passengers on a tram. Luckily, Aoto, another Adapter who was at the scene, stops him with his ability. Akane and Midori are ordered by the Academy to recruit Aoto, but they hear a disturbing rumor about him.

Led by the spirit of the key, Akane, Midori, and Aoto reaches the front of the Gate. There, the Key gives them the option to choose their own fate. However, they quickly learn that the Divine Gate is much more than just something that grants wishes...