Main Characters:
* Anya: A young woman who attends the titular classroom and is struggling to find her place in the world.
* Professor Oz: The mysterious and enigmatic teacher of the classroom who guides students through a magical and dangerous journey.
* Lavinia: Anya's childhood friend and fellow student in the classroom.
* Halstead: A cynical and skeptical student who initially clashes with Anya but later forms a connection with her.
* Jasper: A jovial and lighthearted student who initially seems carefree but has a darker past.
Other Important Characters:
* The Architect: A powerful and enigmatic entity who created the classroom and has a mysterious agenda.
* The Watcher: A creature that protects the classroom and observes the students' progress.
* The Gatekeeper: A being that guards the entrance to the classroom and ensures only the chosen students can enter.
There are also several other characters who play significant roles in the story, including other students, teachers, and creatures within the classroom.
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