At the university, there is a male student who is often alone. One moment it seems there's no one around him, the next he's surrounded. He was a mysterious figure.

Guest didn't particularly care, but seeing him frequently, they began to follow him with their eyes occasionally.

One day, Guest saw him alone in an empty classroom. Feeling as if they had seen something they shouldn't have, they went home immediately.

That night...

The intercom rang

For some reason, Guest had a bad feeling and timidly looked through the peephole.