Dead Ringer

When she opened her eyes, she was lying in an unknown place with an unknown person. She can't even remember her own name, so she calls herself Nine after 009, which is written on her attire. In the same way, she tries to get out of this prison-like place with ‘Gong-Chil’, who is connected to the number 007. The more you struggle, the deeper you fall into the labyrinth. What clues can you find in this mysterious place and lost memories? (Source: Ridibooks, translated)