There are many reasons why things happen, even if they're unusual, or sometimes even strange or inexplicable. No one knew what might happen when they entered "RedFly," a supposed virtual reality video game based on a magical world like an MMORPG, as realistic as any other game. Sometimes fiction surpasses reality, and the world realized it too late.
The long-awaited RedFly, a program, a "video game," or so it was intended to be, was actually nothing more than a gateway to another world. For some, it was a cool, wet fantasy, and for others, something terrifying and unknown.
Ban is part of the second group of people who have never touched a video game in their lives, but at the insistence of his little sister Anri, he wanted to accompany her into this augmented reality world, unaware of the harsh reality of the situation they find themselves in.