Mysterious Recovery: I Became a Ghost Slave Just After Traveling Through Time.

When I wake up, the university classroom becomes the social workplace. When I opened the door, I saw that the wall outside was mottled, like an old office building. "Dong, dong dong" The knock on the door echoed in my ears. No, this is a mysterious recovery! By the time you read this, I will be dead. The one who is still alive now is the ghost slave Huang Yuan...