Arianna was a former servant of House Azelhart until the death of its lord. After the incident, she was relieved of her duties. Jobless and homeless, she wandered from city to city, taking small jobs to survive before she came to Stillsnow to work in a brothel owned by the Obsidians.
Ten years later, she would come across a now-adult Primrose in the town's tavern. After a bit of catching up between the two, she took Primrose to the brothel she worked in and told her of the location on her map as well as how to get there. She would then accompany Primrose on a carriage ride to the Obsidian Parlor before parting ways with her at the entrance, but not before showing her a hidden cave leading inside the parlor.
After Rufus's death, she saw Primrose off at the town entrance and thanked her for her freedom.
- Arianna is also the Latinized form of the Greek name Ariadne, which roughly translates to "most holy".