Penance converts to Christianity early in the story, but it takes place “off stage,” so to speak. The reader sees her exposure and initial interest, but the actual moment when she takes the leap occurs while the story is in Kail’s point of view, away from his experience.
This makes Penance’s conversion far more tolerable than typical “Christian fiction,” which is generally defined as having a conversion of a main character as a major plot point. Changing hearts is a miracle of the Holy Spirit, and thus difficult to portray convincingly in fiction, especially when the author is preachy and determined to resolve a character’s every doubt.
As for Penance, the reader sees her searching and then trusting. It is enough that she reached a decision in that moment and is determined to see it through. She still has doubts and lots of things she doesn’t know or understand about God, but that is an unadorned, realistic depiction of Christianity, which leaves room for character growth.
The placement of the conversion early in the story emphasizes this. Penance’s faith becomes the answer to her questions of self-worth, identity, and belonging, while Kail’s trust in the false god of his culture is betrayed, leaving him unsure of his place in the world.