locked room.
- Or maybe, the murderer is Toshiaki.
- Motive: Haru was going to confess the fraud. Haru felt guilty, wanted to tell the world Toshiaki was the genius. Toshiaki, whose entire identity and twisted devotion relied on remaining the invisible hands of the master, couldn't bear the master ruining his own legend. "You can't tarnish your name, Sensei." So Toshiaki kills Haru to preserve Haru's myth.
- This is deeply Kazehara: "The culprit always has the most understandable motive." (Protecting the beloved's reputation at the cost of their life).
- Toshiaki poisons the final crane.
- How did the room get locked?
- Toshiaki sets up the room. He kills Haru with poisoned tea. (Or Haru dies touching the