Arianna is a small, thin girl with ginger hair down to her shoulders with a white bow tied at the top of her head. She has pale skin and bright blue eyes. She wears a navy dress with a white lace collar tied up with a red ribbon. She also wears white tights, and red and blue striped shoes with red ribbons.
Arianna is a kind and friendly 11 year old but does tend to judge other people very quickly. She has a short temper and doesn't care about what people think of her. She was very out-going and social but after her father died she locked her self off from the rest of the world. She is very close to her brother Tony and after realizing that the townspeople are very nice, with the help from Professor Hershel Layton, Luke Triton and Emmy Altava she becomes friends with lots of kids her age.
A year prior to the events of Last Specter, Arianna's father died. His will was altered by Jakes, so that the land Evan owned was passed down to Clark Triton instead of Arianna. She and her brother Tony continued to live in Barde Manor alone, shooing away any townspeople who came to check on them, under the impression that they thought bad of them because of their father. The specter started appearing in Misthallery shortly after. To make matters worse, Arianna was suffering from an illness that threatened to end her life sooner than later. Tony became very protective of her because of these things and put a mark on the home of anyone who spoke ill of her, and when the specter came it would trash the house. This created the rumor that a calamity witch was living in Barde Mannor, and it spread like wildfire around Misthallery.
Because Tony never told her it was him behind the marks, Arianna started believing that she really was a calamity witch. She remained at the manor constantly, with only Tony and Loosha as company.
When Loosha tried to fight the specter, Arianna would play her ocarina into the pipes of the old water system around Misthallery to calm her down.