During his summer vacation, middle school student Nagasumi Michishio travels to the Seto Inland Sea. One day, while swimming at Mio Sun Beach, his leg suddenly cramps. No one is close enough to notice his desperate screams for help, and so he sinks into the ocean, where he is left to drown alone. Just as he loses consciousness, however, a mermaid appears and saves his life. That night, Nagasumi is visited by his savior, a girl who introduces herself as Sun Seto—a mermaid from a yakuza family. As it turns out, under mermaid law, a mermaid whose identity is revealed to a human must be punished by execution. To avoid this harrowing outcome, the Seto family propose a solution: Nagasumi must marry Sun or die at the hands of Gouzaburou, Sun's father and boss of the Seto clan. Faced with no other option, Nagasumi takes her hand in marriage. Now, the newlyweds face the difficult task of keeping their relationship secret. Between Gouzaburou's unending attempts on Nagasumi's life and the eccentric antics of a slew of antagonists, a genuine and innocent love blossoms between the pair as they adapt to their new life. [Written by MAL Rewrite]

The Society for the Study of Modern Visual Culture, otherwise known as Genshiken, is now under the charge of a more confident Sasahara. Things have changed in between semesters, and the otaku club now has a new otaku-hating member named Ogiue. Sasahara's initial goal of starting a doujin circle and selling those fan-made magazines at the next Comic Festival becomes a reality, but reality is a cruel master... who apparently crossplays. Afterward, the club is abuzz with talk about Tanaka and Ohno's relationship, which takes a hesitant step forward. (Source: Media Blasters)

Mao Onigawara is a happy 8-year-old grade-schooler and the granddaughter of Chief of Staff of Ground Defense Force. Equipped with her cloverleaf-shaped badge which enables her to transform (but gives her no special power whatsoever), Mao and her best friends (granddaughters of Chief of Staff of Air and Marine Defense Force, respectively) will defend Japan against the invasion from "cute aliens," who are way too cute to be dealt with by regular armed forces. (Source: ANN)

In the backwater town of Bellforest lives a 14-year-old boy named Renton Thurston. He desires to leave his home behind and join the mercenary group known as Gekkostate, hoping to find some adventure to brighten up his mundane life. However, stuck between his grandfather's insistence to become a mechanic like him and the pressure of his deceased father's legacy, the only excitement Renton finds is in his pastime of riding the Trapar wave particles that are dispersed throughout the air, an activity akin to surfing. Everything changes when an unknown object crashes through Renton's garage, discovered to be a Light Finding Operation—a robot capable of riding the Trapar waves—specifically known as the Nirvash typeZERO. Its pilot is a young girl named Eureka, a member of the Gekkostate, who requests a tune-up for the Nirvash. Their meeting sparks the beginning of Renton's involvement with the Gekkostate as he takes off alongside Eureka as the co-pilot of the Nirvash. [Written by MAL Rewrite]