Forth game in Amnesia otome visual novel series.

This story takes place on a fictitious world, in a fictitious city built in a fictitious country. August 1st. The protagonist awakens from her sleep, only to realize that she no longer possesses any memories prior to that day. She does not know who she is, or what kind of life she had been living. She cannot even recognize any of those who claim to be close with her. Then, a young man calling himself “Fairy” appears before her… Several days later. At Meido no Hitsuji, where the protagonist works her part-time job, her superiors announced a [Concept Event] project. The project was initially her idea, but she can no longer remember what, exactly, it was. Without any clues about what the project entails, she has to begin preparing for the event with her fellow staff members…