Amnesia

A young woman who fainted at work wakes up in the café's back room with no recollection of her life or the people in it. She soon finds out that Shin and Toma are two of her friends, and they are contacted to assist her in getting home securely. When she is by herself, she meets Orion, a phantom boy who can only be seen and heard by her. He explains that his accidental visit to her world caused her to lose her memories, and he makes a promise to assist her in regaining them. She may find it harder than she thinks to restore her lost memories without frightening people close to her. She must be careful not to raise the suspicions of the mesmerizing Ikki, the quick-witted Kent, and a mysterious figure who lurks in the background, in addition to the gloomy Shin and the protective Toma. Her fractured memories gradually reemerge as her amnesia draws her into the lives of these guys, and the secrets surrounding her situation slowly becomes clear.