Naïve 16-year-old Mamori Tokonome is accustomed to being teased at school for having an unfortunate surname that can also be read as virgin. However, young Mamori will soon have to get used to being teased in other ways... Kidnapped during gym class, Mamori wakes up only to find herself stranded and under attack on the exotic island of Mermaid. Luckily, enigmatic fellow castaway Mirei Shikishima knows exactly how to take the lead—through a passionate kiss, Mirei unleashes Mamori's Exter transformation abilities, turning the innocent red-head into a battle-ready cutlass through the power of arousal. The duo will need to tap into that power as Mermaid Island is full of potential friends and foes: Charlotte, the sadistic Liberator of an Exter harem; the gluttonous and crafty Meifon; the mysterious but charismatic Akira Hiiragi; and the erotic biker duo Lady Lady. Mamori and Mirei's powerful and intimate embrace is the only way for the pair to ensure their survival on this scandalous island.

On the outskirts of the country of Helvetia rests the tranquil town of Seize. Upon its cobbled streets, citizens go about their daily lives, undisturbed by the increasingly tense military relations between Helvetia and the neighboring Roman Empire. It is under these circumstances that the 1121st platoon of the Helvetian army, stationed at the Clocktower Fortress in Seize, receives a new recruit in the young and spirited Kanata Sorami. Having joined the military to fulfill her dream of learning to play the bugle, she excitedly accepts the tutelage of the Sergeant Major, Rio Kazumiya, who happens to be a skilled trumpeter. Working alongside them are the aloof mechanic, Noël Kannagi, the feisty gunner, Kureha Suminoya, and the compassionate Captain Felicia Heideman; together, they experience the beauty of life in Seize and the lasting joy of a community that has persevered in spite of the crumbling world around them.

In 2035, an incident known as “The Burst” occurs at a Japanese research facility, giving birth to the rapidly expanding, consuming, and self-replicating Matter. Snaking its way through the remains of dams and military facilities in the Kurobe Gorge, the hostile Matter is besieged by task forces trying to prevent it from reaching the ocean and mercenaries seeking the truth behind its existence. Aiko Tachibana lives under constant medical surveillance after being rescued from the Matter. She spends her days waiting out her recovery by making paper planes. Soon, her daily life at school is disturbed by the arrival of transfer student Yuuya Kanzaki, who proceeds to point out a number of inconsistencies regarding her body. Why is she never injured, and why does she suddenly no longer need her wheelchair? He claims that there is more to her existence than she has been led to believe, and that she alone holds the key to ending The Burst. With many factions now interested in Aiko, she and Yuuya must gather allies and embark on a dangerous pilgrimage into the heart of the infested gorge before the net can close around them. To escape the conspiracy moving against them, the pair must face off against the Matter—an enemy that flows like water.

The Great Kanto Desert, a sweltering wasteland of nothing but ruins and sand, is all that remains of post-apocalyptic Japan. The once fair population has been left to cling to the inhospitable dunes for survival. At least, that is the case for normal people. For those who have spent a little too long in the Kanto sun, the desert offers a wondrous opportunity to make a name for themselves. One such person is the masked handyman Sunabouzu, or Desert Punk, who has forged a legendary reputation for always finishing his jobs, no matter the nature or cost. Cunning and ruthless, he has become a force of crude destruction to the other desert people. However, the Vixen of the Desert, Junko Asagiri, discovers that Sunabouzu is not without his weaknesses—he is easily swayed by his insatiable lust for large-breasted desert babes. Following their chaotic adventures through the Kanto Desert, Sunabouzu features a bizarre cast of personalities who entertain themselves with senseless violence and perversion in a world long destroyed by their forefathers. And just like them, they have not learned a damn thing.