Even though Rowan has gotten accepted into the Magus Society here she questions and is overwhelmed by her flaw as she questions if she is worthy enough to truly be at the school and be surrounded by such talented people.
As classes start she finds herself struggling to fit in with her peers who all seem to hate her for not having an ability. As the school year progresses an series of weird events lead up to their being an attack on the society (This is where the Antagonist appears). The attack also causes more of her peers to doubt her and the protagonist to doubt herself more as she was unable to do anything to help during that time.
As it becomes clear the Society is under threat, Rowan realizes she needs to see her worth and confidence if she wants to gain the trust and respect of her peers and help the Society face the threat.