Souji Mitsuka is an ordinary high school boy who has an obsession for twintails. One day he encounters a mysterious girl named Twoearle, who is from a parallel world, when monsters appear in his town and declare that all twintails in the world belong to them. These monsters feed off "attribute strength," the spiritual energy of humans. Twoearle entrusted Souji with Tail Gear, imaginary armor initiated by powerful twintail attributes. With the armor, Souji transforms into a girl and twintail warrior branded Tail Red, to protect Earth.

Twintails: the glory of all mankind—or at least that is what first-year high school student Souji Mitsuka believes. At school, Souji spends most of his time daydreaming and rating girls' twintails, even going as far as creating a club dedicated to the hairstyle. His obsession does not go unnoticed, however; when monsters from outer space attack Earth and claim the world's twintails for themselves, a strange woman named Twoearle enlists Souji to fight back using twintails of his own! By transforming into the twin-tailed warrior Tail Red, Souji combats the vicious alien organization known as Ultimegil, whose main goal is to colonize Earth and steal everyone's spiritual energy, or "attribute power." Alongside fellow twin-tailed fighters Aika Tsube and Erina Shindou, Souji must find a way to defeat the invading army and defend the twintails he holds so dear. *Note: The volume count includes the volume 4.5.*

An anthology series of *Yahari Ore no Seishun Love Come wa Machigatteiru.*

One day, Haruka Fujimi, a popular high school girl who is a model and an influencer, decides to make a movie, thanks to the suggestions of her senior at school, Chiharu Enjoji. However, it turns out to be a "special effects movie" with people walking around in monster suits and models exploding all over the place! Haruka felt tricked by Chiharu, but she becomes friends with the unique members of the club and starts to see the charm of their special effects...? (Source: Sunday Webry, translated)

Side story of Ore, Twintail ni Narimasu. bundled with the limited editions of the 1st, 3rd and 5th Blu-ray/DVD volume of anime.

In a time long ago, there was an era where beautiful goddesses fiercely competed for the throne of world rulers. At some point, the goddesses with fangs, disguising themselves with the façade of love, began to peacefully guard the human world. A young boy named Soujou Shouma, encounters and falls in love with a goddess who secretly came to the human world. After making a promise to meet again someday, he works hard to grow and become a man worthy of the goddess. Even as a schoolboy, he is appointed as the president of a company. However, in the modern era, abnormalities occur in the divine realm of the goddesses, known as the Heavenly Realm. The uncontrollable goddesses engage in violent battles reminiscent of ancient times to decide the next creator god – the ruler of the Heavenly Realm. This conflict’s flames even spread to the human world. Upon learning of this, Shouma, in order to fulfill his first love and protect world peace, decides to utilize his company in a special way for the goddesses. He teams up with one of the strongest goddesses, Elvina, who shares his interests, and as the company’s president, joins the battles! (Source: Shogakukan, translated)

SSSS.GRIDMAN NOVELIZATIONS is a 2-volume spin-off novel series based on SSSS.GRIDMAN. The story takes place some time after episode 8 of the series.