Description: You play as a young man named Akito, who briefly finds himself trapped in a strange dimension where he encounters an Angel. Shortly afterward, he returns to reality, but it seems that part of his memory has been erased. Everything feels unfamiliar and strangely distant. He can barely understand where he is! Then a girl suddenly sits beside him and introduces herself as his stepsister, Aiko. Akito begins questioning her about their lives together. He learns that they live with their adoptive mother, with whom he apparently had some kind of argument just days ago. Now he must somehow rebuild his life despite his confusion and uncertainty about what awaits him next!