Kaname Okiura, a student of Prefectoral Umineko Shougyou High (Umishou for short), joined the school's swimming club in order to learn how to swim, but the club is filled with weirdos, let alone who can teach him swimming. Then, a sunny, happy-go-lucky girl named Amuro Ninagawa who transferred from Okinawa joined the club. Her extraordinary underwater speed and unorthodox swimming style (plus her personal habit of nude swimming—a powerful magnet to teenage boys) surprised every club member, especially Okiura, because she reminds him of a mermaid-like creature he saw only once in his early childhood. (Source: ANN)

A new Sayonara Zetsubou Sensei OVA.

Reaching a period of life where they are neither a child nor an adult, 12-year-old Hanabi Ayase and Aoi Yui meet with life-changing events. Due to the mischievous demeanor of her male classmates, Ayase does not think highly of the opposite sex. However, her perspective begins to change after she is paired with the kind-hearted Takao Yuuto for a class assignment and unexpectedly shared their first kisses with each other on the school rooftop. With her best friend discovering love, Aoi yearns to seek her own. She finds herself falling in love with the rash Kazuma Hiyama after protecting her from a rejected suitor who had talked behind her back. 12-sai.: Chicchana Mune no Tokimeki follows the four in this phase of adolescence. As they grow up alongside each other, this sweet romance depicts the innocence and excitement of first love.

Five separate worlds—Black, White, Green, Red, and Blue—are linked by the Halo and exist in a harmonious balance. However, the Halo suddenly opens in an event known as the World Connect, threatening to destroy the universe. Coming under attack by Ouroboros, an alien species that wishes to accelerate the universe's end, the five worlds recruit girls with special abilities called Exceed to defend against them. Saya Sougetsu, a young girl from the Blue World of Earth, is one such individual able to wield Exceed power. Believing this to be her chance to make a difference, Saya eagerly joins the defense force. There, she meets Amane Ayashiro, another girl from Earth, as well as a selection of fighters from the other worlds. Faced with a formidable foe, the girls must prove that their newfound bonds are strong enough to save the future.