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The series' protagonist Annelotte is seeking the head of reigning Queen Claudette for revenge and justice. Following her swift defeat and imprisonment Annelotte is now building a rebellion army to take on Claudette once more!
Two altered humans, Uno and Yuuna, take on ARCA's deal to service their debt.
Tokonome Mamori is transferred to "Mermaid"—an artificial quarantine island for people with superpowers. When Mamori is attacked, a newly transferred girl named Mirei saves her. The enemy doesn't stop, however, and the two are soon cornered. Just when they think all hope is lost, Mirei kisses Mamori, and Mamori turns into a sword. Mirei then wields the sword and launches a counterattack against their enemies.