Season 1

Ryoka is awakened by flurry of text messages from her mother! Panicked and rushed, Mom is clearly concerned for Ryoka's safety but she is not too keen on letting her daughter know why. The world might be ending! And there might be an unidentifiable being on the roof of their apartment building!

1. 

   1. Confinement

   2024-09-07 · 13m

   When Ryoka, a high school girl, wakes up, she is left behind in a sealed-off apartment. A message from her mother tells her that there is a mysterious creature called "X" in the apartment.

2. 

   2. Reunion

   2024-09-14 · 13m

   When Ryoka hears that her childhood friend Shuhei is also left behind in the apartment, she calls him. What is the ecology of "X" that her mother told Ryoka as she waits for Shuhei to join them?

3. 

   3. Brainwashing

   2024-09-21 · 13m

   Ryoka and Shuhei manage to escape from "X" just in the nick of time. They try to leave the apartment, but suddenly lose consciousness.

4. 

   4. Encounter

   2024-09-28 · 13m

   X has good hearing and walks on two legs. Ryoka is perplexed by the fact that X has different characteristics than what she saw in her dream, but first she heads to the fourth floor where Shuhei is waiting to meet up with her.

5. 

   5. Resistance

   2024-10-05 · 13m

   Thanks to Shuhei's quick thinking, he manages to distract X's consciousness. However, X's pursuit does not stop, and Shuhei is eventually captured by X.

6. 

   6. Light

   2024-10-12 · 13m

   Ryoka and Shuhei make use of X's blindness and reach the elevator safely. What awaits the two on the 31st floor, which should not exist?

7. 

   7. Inheritance

   2025-02-22 · 13m

   Ryoka and Shuhei have made it to the 31st floor, which shouldn't exist in the apartment building, and have cleared level 2.

8. 

   8. Signpost

   2025-03-01 · 13m

   Ryoka discovers a candy house. There, she finds a witch who is a level 3 X. Ryoka is thrown into a loop again and heads off to confront the witch.

9. 

   9. Witch

   2025-03-08 · 13m

   Ryoka and Shuhei fight the witch to save the captured Hansel and Gretel. The witch uses spider webs to immobilize the four of them.

10. 

    10. Foreknowledge

    2025-03-15 · 13m

    After defeating the witch, Ryoka and Shuhei take the elevator to the 32nd floor.

11. 

    11. Blank

    2025-03-22 · 13m

    Without any clues from the notebook, Ryoka and Shuhei challenge Level 4. Ryoka is driven to despair by the fear of being killed again.

12. 

    12. Future

    2025-03-29 · 13m

    Having grasped the true identity of X, Ryoka and Shuhei make a desperate attempt to conquer Level 4.