Aunt Mari's appearance is unknown, aside from the fact that she is an older woman.
Aunt Mari is known as a gossip. She is easily intrigued by other people's affairs and enjoys hearing about young romance.
Vivi has known Aunt Mari for a long time and was happy to see her when they crossed paths.
One Piece novel HEROINES
After Fata and Koza accidentally dropped the former's love letter to Vivi off of a balcony, and it fell into the hands of the passersby below, including Aunt Mari. She read it and confronted the pair about who wrote it. When Koza took the blame to save Fata from embarrassment, she was surprised and amused, pressuring him to confess. King Cobra, Pell, and Chaka arrived to speak to Koza about Levely in the middle of the affair, and Mari shared the letter with them. When Vivi arrived, Mari spoke to her knowingly, but before she could share what had happened, Koza gave Vivi Fata's letter himself.
- One Piece novel HEROINES Chapter 3, Mari finds and reads Fata's love letter to Nefertari Vivi.