Turnaround System

The protagonist is fat, but he used to be thin, fat for no reason; the girl knew him and was once a friend, but she does not exist in his memory; the world used to be chaotic, with all kinds of ghosts and monsters running rampant, but now it is peaceful and peaceful; what happened in the past? Who is myself in the dream? Where are Longyuan Pavilion and Sanctuary? Does the system assist the protagonist or enslave the common people? What is hidden behind the terrifying thought? When the protagonist wakes up, can he control his own destiny?