One day, Yuuki heads out to deliver an item to a client. When Pecorine and the others meet up with him, they discover that the client is Tsumugi, a member of the popular idol group Carmina, and Yuuki is being made to wear a cute outfit at her behest. The group is naturally confused, but there seems to be a reason behind it...

The Shadows on Monster Isle form a swarm with the golems and launch an attack on the islanders. Meanwhile Pecorine suddenly disappears from sight. While the Caon members, along with Yuuki and the others, are putting up a desperate fight to protect the island, Kasumi comes up with a secret plan to stop the Shadows' progress.

Pecorine confesses to the people of Landosol that she is the true Princess Eustiana. In order to reclaim her name and throne, she vows to overthrow the imposter princess—the Omniscient Kaiser. However, she must first fight against the captain of Nightmare, Jun, who has been brainwashed...