The story is about an academy who’s facing a huge crisis in front of them. A terrifying creature that can be considered terror is haunting them. Severals group’s rally was sent to the cave where the the rumoured medusa reside, but they didn’t returned. The head of student council, Fumiko, decided to go to expedition site to save the the groups. But something is odd, the medusa only turned the male soldier into a stone while letting the female alive. Turns out that medusa planned to plant their seed into them. After a rough “battle” they finally won. But what they just fought is actually just the lowest type of medusa. Will Fumiko and her friends be able to overcome this horrifying crisis?