Riri is overjoyed that Yuyu is now her Schutzengel, but can she hold up under Yuyu's harsh training? Then, when a powerful Huge attacks, Riri gets a glimpse of Yuyu's secret.

Riri finds a mysterious girl in the remains of a dead Huge. The amnesiac girl quickly grows attached to Riri, who devotes herself to taking care of her. But just who is this girl, and how will Riri's legion deal with her absence?

As Riri and the others continue to grieve, Yuyu isolates herself, tormented by visions of Misuzu. As the Huge attack Yurigaoka as they never have before, Yuyu is forced to question the truth of her relationship to her late Schutzengel.