——When I woke up, I had lost my memory.

　 　 　 　 All Guest knows now is that this is a world covered in pure white snow. And that their finger is tied to the young man in front of them—Manato—by a "Red String." 　 　 "Oh, this? A safety device, I guess. It was there when I realized... but it keeps us from getting separated, so it's handy, right?"

"Me? I'm your childhood friend, your old flame, and your partner at work."

"There's nothing here, right? But you'd be surprised what you find if you dig... Let's go together, for the sake of survival." 　 　 　

"I'll tell you everything you need to know."