From The Heretic Knowledge Vault
Ms. Codoin is one of two sisters (the other being the recently, and thus far inexplicably, deceased Rebekah), exchange students at Emerylon University, who play a part in the mysterious disappearance of Father Egbert, former assistant Abbot at the Veracian mission in Kiyoka, peculiar suicide perpetrator, and general plot MacGuffin. She and her late sis were among the last people to see Egbert as he used a warp gate to flee Kiyoka for parts unknown. Unfortunately, she and Becky were sufficiently drunk at the time that their testimony on what happened there is suspect.
We don't know what Hannah is doing at the University, but she apparently didn't join her sister in traveling south to Gervasiel and the archaeological dig where she met her fate. That means she's still out there somewhere, so we might see her again.