Far beneath the prestigious violin school, St. Cecilia Academy, lies an evil secret. A monstrous colon-slurping demon lives underground, granting power to the one who plays the demon violin, Kannone, in exchange for copious amounts of its favorite meal. To fulfill his half of the bargain, the headmaster begins an ambitious program to enlist only the most beautiful women into his special classes. But Yukina is not about to lie down and take it - she has the holy violin of St. Cecilia and she's going to fight back!