Mari introduces herself as a net idol. She says she agreed to help Neo because he said she would 'be his queen' when he became the prince of the Digital World.
Mari appears as the second of the Alias III. Before running into Taichi, she catches Igamon before he can deliver a warning to the Holy Angel Castle. When she sees Taichi, she acts stupid and does her best to distract and slow Taichi down so that he can't reach the Holy Angel Castle to help in its defense. After he finds her out, she stops playing around, and Rosemon almost wins against Zeromaru. As Igamon tries to help, Mari stomps on him, calling him weak and foolish, and telling him to go die. Angry at her horrible treatment of the brave Digimon, Zero uses Igamon's shuriken to redirect Rosemon's Beauty Shock, allowing him to defeat her and proving that Igamon is not useless.
Mari joins Hideto and Sigma against Neo, though only after he admits he was using the three of them for his own purposes.
Due to Mari's partner, she likely owns a Pendulum 4.5 Wind Guardians.