A shy cat girl gets yanked into a neon music city and immediately has to keep up with a rabbit who's too smart, a dog who lives online, and a sheep that might not be real. The band chemistry writes itself because nobody is trying to be cool, they're just locked in together trying to make something that works. It's pure, unfiltered joy about four girls who have no business being a band but keep showing up anyway.

Cyan is a gothic lolita cat girl who loves a rhythm game, until she is pulled inside it and lands in Midi City, a metropolis where music rules everything. Though she has real guitar talent, she lacks the confidence to chase her dream of playing in a band. After being scouted by Maple Arisugawa, head of a music agency, Cyan teams up with Chuchu, a rabbit girl honor student, Retoree, a shy dog girl and net geek, and Moa, a sheep girl said to be an alien. Together they form Plasmagica and set out for the top. Armed with special instruments, they battle rival bands such as Shingan Crimsonz and Trichronika, all competing to perform atop the city's tallest tower, while a sinister plot threatens to plunge Midi City into darkness. The result is a comedic fantasy music series about a band hoping to make it big.