Every 60 years, the heavens conduct a sacred ritual called ETM12. This custom involves selecting worthy Eto-musume—celestial beings representing different animals—to become one of the members of the Chinese zodiac, or Eto-shin. However, since the first ETM12 two thousand years ago, the original batch of Eto-shin reigns with no one being able to replace them. Nyaa-tan is a cat Eto-musume who aspires to become a member of the zodiac in the ongoing ETM12. Fulfilling her ambition requires her to secure 12 seals, one for each Eto-shin. To that end, she must win various types of battles using Sol/Lull—divine energy created by people's positive emotions. This task is not easy however, as her powers as an Eto-musume are far below the abilities of a single Eto-shin. As such, she needs a constant source of energy. But in a chance encounter, Nyaa-tan meets Takeru Amato, a man who has just transferred to the apartment where she is secretly staying. To Nyaa-tan's delight, Takeru discovers that he gives out high quality Sol/Lull—something that sets him apart from most people. With this, the story of Takeru and Nyaa-tan begins. As Takeru supports Nyaa-tan in her dreams, he meets the Eto-shin and begins to uncover a mysterious past.

The great music adventure in Show by Rock!! begins after Cyan decides to play her favorite rhythm game and suddenly gets sucked in, finding herself in a world called Midi City where music reigns supreme. She learns that anyone who delivers amazing and powerful music also has the ability to control the city. However, not all music is pure. An evil plan is set in motion to engulf the whole Midi City in darkness. Is it too late for Cyan to do something? Cyan Hijirikawa always regards herself as nothing but an ordinary girl living in a mediocre world. She has great talent and extreme guitar skills, but she also lacks the confidence to take the first step in realizing her dream to play in a band and be a music millionaire! Little did she know that an eminent power resides deep within herself—the power to defeat evil with her magical music! Join Cyan, Chuchu, Retoree and Moa in a world where music is everything.

Upon waking up, Subaru Natsuki finds himself in a parallel reality of the fantasy world he has come to accept as his own. Despite being familiar faces, Subaru's friends are vastly different, especially as they enjoy the life of modern society that he knows all too well. This mysterious world captures the intrepid boy's interest nonetheless, and a clash between his antics and the dubious inhabitants soon leads to all sorts of amusing scenarios.

Catian Eris is now on a mission to learn about Earth games and how they are played, but she seems to think that bets have to be placed every time. And while some bets are material items, eventually the Catians learn about betting items of clothing...