Valkyrie Drive: Mermaid: Season 1

Mamori Tokonome, a girl who was diagnosed with an irregularity in her body, is captured by agents and taken to a remote island known as Mermaid. There, she is attacked by two girls named Miyasato and Kouzuki, the former being a Liberator who arouses the latter, an Exter, to transform her into a gun known as a Liberator Arm. Just then, another girl by the name of Mirei Shikishima arrives on the island, protecting Mamori by transforming her into a sword, allowing her to defeat Miyasato and Kouzuki

Following their battle, Mamori and Mirei are restrained by two other Liberators. While Mirei is locked away in a disciplinary room, Mamori wakes up in the care of Kasumi Shigure, commander of the Welter, who explains that all the girls on the island are carriers of something called the Armed Virus, who are divided into Exters, who can transform into weapons, and Liberators, those who can wield them. Charlotte Scherzen, one of the Liberators from before, then informs Mamori that she is to undergo

Mamori and Mirei are picked up by Meifon, who takes them to a small town run by Torino Kazumi, who takes care of girls who don't want to or are unable to stay at Veste. Meanwhile, despite Kasumi's attempts to keep it a secret, Charlotte learns about Meifon repeatedly stealing supplies from Welter, commanding Kasumi to go and apprehend her. The next day, as Kasumi arrives in Torino Town to search for Meifon, Mirei offers to take responsibility for the theft and turn herself in. When Charlotte pre

Surrounded by Welter soldiers, Rain kisses Mirei to transform into the Disarmment Buster Arm that forces Exters out of their weapon states, while Lady J uses her skills as a motorcycle to fight back Charlotte and Kasumi. Just then, Akira Hiiragi, Welter's governor and allegedly the only male on Mermaid, arrives to prove Mirei's innocence, having encountered Meifon earlier, and recalls the troops, much to Charlotte's ire. After Lady Lady take their leave, Mamori starts taking an interest in Akira

Mirei, Mamori, and Kasumi come across a girl named Nimi Minimi who, after running away from the castle when Charlotte tried to force her and her girlfriend Noe Oya into separate partnerships, somehow wound up in a giant form. Nimi is brought to Atelier Torino, where she manages to get along with everyone despite her gigantic form. The next day, as Nimi suddenly grows even larger, Mamori encourages her to go and see Noe and tell her how she feels. This naturally causes panic as she approaches the

Meifon works with her partners in crime, Hyouko Yundou and Futaba Kirii, to steal more goods from Veste while also making money from gambling. Feeling she can make a killing from bets, Meifon arranges for Mirei to enter a beauty pageant being held at the Mermaid Festival. On the day of the festival, Charlotte gets chosen as the winner, with Meifon deducing that Hyouko and Futaba had switched out the ballots in order to kiss up to Charlotte. Discovering what had happened, Mirei and Mamori face of

Stressed from work, Akira, who is revealed to be a woman, sneaks out to be spend some time with Torino, keeping her identity a secret from Mamori and Mirei. Spending the night in Mamori's room, she recalls how her mother arranged for her to act like a man upon arriving at Mermaid in order to stay safe. The next day, some rebellious girls take one of the Ritters hostage in the building where Akira is keeping her male clothes. As Charlotte and Kasumi argue over how to approach the situation, Mamor

Lady Lady are asked by Akira to investigate a location said to contain the secret of Mermaid, bringing Mamori, Mirei, and Meifon along with them. Uncovering a hidden cave, the girls find an underground construction plant, where they are attacked by an Artificial Arm that Mirei finds all too familiar. Unable to drive with Mamori following the ordeal of her attack, Mirei unleashes the true ability hidden in her body to fight the Arm, but is still overpowered by it. However, Mamori, determined to p

Momoka arrives on Mermaid under the guise of a new transfer, quickly demonstrating her Exter abilities and becoming a part of Charlotte's Adel team. Quickly deducing Akira's true gender, Momoka manipulates Charlotte into confronting Akira in a battle in order to expose the truth. Noticing something about Momoka's power, Akira brings out the full strength of her Artificial Arm, Sri, against Charlotte and Momoka and manages to defeat them. However, Momoka brings out her true power as a third gener

Kasumi recalls how she and her partner Hibiki Kenjo, who has been in shock ever after being attacked on the island, was protected by Akira and made commander of Warter. With Akira's gender exposed, Charlotte, under Momoka's influence, declares herself the new governor, sending soldiers to capture the residents of Atelier Torino, while Momoka and her allies use a mysterious power to inspect people's bodies for something. As Mirei infiltrates Feste, having Mamori take Akira somewhere safe, she is

As Momoka, who were once a part of the same experiments as Mirei, prepares to attack, Lady Lady show up to fight against her, but find their attacks ineffective against her Soldier Arm. Momoka and her allies then kidnap Mamori, learning of the potential within her and deciding to keep her to herself. Meanwhile, Mamori recalls when she was in the same organization as Momoka, having been exiled after refusing to kill others and later sent to Mermaid due to possessing the Armed Virus. Blaming Mirei

Mirei struggles to fight against Momoka as she wields Mamori against her, but is aided by Kasumi, who is finally joined in battle by Hibiki, as well as Lady Lady and Meifeng. However, Momoka uses Mamori's Valkyrie ability to absorb other girls into her arm and become stronger, overwhelming the others in a single shot and absorbing them. Inside the blade, as the captives are attacked by tentacles that draw the Armed Virus out of them, providing Momoka with enough power to even destroy a satellite