New nurse, Youka Domyoji, has been working as a new nurse for two months. When she woke up in the nap room to get ready for the night shift, she was locked in the nap room by something. The temperature in the room continues to drop and sensing that her life is in danger, Yoka attempts to escape from the nap room. The corridor of the hospital, beyond the door that opened, was an alien world with strange shapes wandering around.

Will Yoka be able to return to her world...?