1. Kill me... please.

A young girl named Rachel awakens at the bottom basement level of a closed-up building. She's lost her memories and has no idea why she's here.

2. Your grave is not here.

Rachel is saved from an attack by Danny, the man calling himself her doctor, when Zack appears. She asks Zack to kill her, and he agrees as the two of them start to search for a way out of the building.

3. I swear to God.

After arriving at the small room in the back of the reference room, Rachel encounters Eddie, the digger of graves and master of Floor B4. Eddie claims that he knows what happened to Rachel's parents and why she's in this building.

4. A sinner has no right of choice.

The door to Floor B3 opens to reveal a space like a prison cell, enclosed by pure white walls and iron bars. The moment Zack strikes the locked door before them with his scythe, the duo are barraged by machine gun fire.

5. Don't let me kill you just yet.

Rachel finds the key card to get them out of the poison gas room, but Zack handles it too roughly and breaks it. The hourglass announces that their time is up, and a powerful poison gas begins to pour into the room.

6. Zack is the only one who can kill me.

After willingly shooting a dangerous drug into his arm so that they could move forward, Zack begins to grow overwhelmed by the urge to kill. But with the last traces of rationality left in his mind, he tells Rachel, "Don't let me kill you just yet..."

7. Who are you?

After slashing open his own belly, Zack is left without the strength to stand, so Rachel sets off alone into Floor B2 in search of something to stop his bleeding

8. Yeah..., I'm a monster.

Rachel heads to Danny's floor with Gray, the priest, to search for something she can use to treat Zack. However, Gray tells her she must undergo a series of tests to get there.

9. There is no God in this World.

Danny, who Zack thought he killed on Floor B5, shows up and offers Zack a deal: Rachel's eyes in exchange for medicine to treat his wound. Meanwhile, Rachel finds Zack's room on Floor B6 and retrieves the knife he asked for.

11. 'cause you are my God, Zack.

Gray proclaims himself closer to being a God than anyone else and sentences Rachel to burn alive for the things she did to the other floor masters. Hanging on her cross, Rachel insists that she's not a witch and that she only wants Zack to kill her.

12. Try to know everything about her

Floor B1 looks like an ordinary residence. After following a trail of blood to what appears to be a living room, Rachel suddenly panics. She pressures Zack to kill her immediately, then passes out. Then Danny appears, only to shut Zack out of the room and tell him, "If you succeed in learning everything, I'll open the door." So Zack sets off to search the floor on his own for the truth...