Mamimi Tanaka is a third-year high school student and a member of the unit L'Antica within The IDOLM@STER Shiny Colors. She has a striking, punkish appearance with short purple hair styled into twin tails and a bowl cut, purple eyes, and a choker. Her image color is light brilliant violet. Mamimi gives off a lazy and indifferent vibe, often speaking in a listless tone and actively avoiding anything she finds troublesome. She maintains an apathetic attitude toward most things outside of her own hobbies and has a self-proclaimed identity as a "bad girl," sometimes purposefully misbehaving to match that image. However, beneath this contrarian exterior, she does care about people in her own subtle way and is willing to put in the necessary effort when it truly matters. She was raised in a privileged household and underwent a wide variety of lessons from a young age, including piano, which gave her a sharp sense of pitch and a natural musical ear. Despite this background, Mamimi initially lacks clear goals or aspirations, drifting through her idol work with little visible enthusiasm. Her role in the story centers on her gradual growth within L'Antica, where her interactions with fellow members Kogane Tsukioka, Sakuya Shirase, Yuika Mitsumine, and Kiriko Yukoku help draw out her hidden sense of responsibility and care. Over time, she shows more willingness to contribute to the group, such as taking initiative to shop for outfit decorations, revealing that she pays attention to and cares about her teammates even when she pretends not to. Notable abilities include her strong musical ear from years of piano training, a tendency to tease and wander, and a punk style that sets her apart visually and thematically within the idol lineup. Her development is marked by a shift from pure apathy to a reluctant but genuine dedication to her unit and her craft.