A girl born in a good family named Silvia had entered a university
and started to live independently. Now she fully enjoys her student life.

On one holiday, Silvia is on a car trip with her university friends.
As is often the case of novice drivers, however, they reset their
destination to a more distant city and end up being stuck in a deep fog.

While being at a loss, Silvia finds light in the fog.

Silvia desperately runs toward the light ignoring her friends' warning.
When she comes to her senses, she finds herself standing in a hallway of a mansion.