**Background:** Mari is a third-year student whose parents (her mother and Italian-American father) manage a hotel chain, Ohara Hotels and Resorts, including Hotel Ohara on Awashima Island (based on the actual Awashima Hotel, currently the Wyndham Grand Awashima) where Mari lives in a suite, which proves her upbringing from a very wealthy family.[1] She's childhood friends with Kanan Matsuura and Dia Kurosawa, knowing them since elementary school. Due to her part Italian-American upbringing, Mari speaks with an accent and often inserts English words into her speech every few lines (in the English dub, the English words are replaced with Italian words).[2] She also tends to speak in the third-person. She is first seen in the first episode flying in the family's helicopter, before formally appearing in Episode 3, where she becomes the director of Uranohoshi Girls' High School (despite still being a student) after her family contributed a large amount of money to the school. Season 1 Episodes 6, 8 and 9 reveal that she, Kanan and Dia formed a school idol group two years ago while on their first year, Kanan having convinced Mari to join. However, Mari had suffered an injury right before an important performance, so Kanan and Dia decided to step down and not perform. Later on, Mari leaves Uchiura to study abroad after the three disband their school idol group. Once Mari learns the truth in Episode 9, she confronts Kanan over it, but both reconcile with the other and decide to become school idols once again, joining Aqours alongside Dia. <hr> **Personality**: Mari has a cheerful, eccentric and mischievous personality, makes many jokes, and often prefers to work by herself. She always keeps her chin up when faced with hardship so as not to burden others, and is ready to try her hand at anything. However, as a half-foreigner, she does not feel that she is very suited to being a Japanese-style idol. Despite Mari's cheerful personality, there are times when she can be serious as shown in Season 1 Episode 9. Mari speaks with an accent, and she has a high, cheerful voice. Mari often inserts English words (Italian in the English dub) into her sentences, but when she is sad or serious, the pitch of her voice becomes lower, she loses her accent, and she uses English words less. <hr> **Appearance:** Mari has a slim figure with light blond hair that she has tied into a braided headband with a loop on the left side and bright green eyes.

- Her favorite genre of music is industrial metal, as stated in her official introduction and shown in Season 2 Episode 2.