MIMI
Like every self respecting Irken soldier, Tak has a SIR unit. Mimi is Tak's customized SIR, obviously modified from a SIR's original frame, Mimi was probably constructed by Tak, who previouslt demonstrated her engineering skills by building her own customized Voot Runner. Judging by her name, it can be inferred that Mimi has female programming.
Like Gir, Mimi has an Earth disguise in order to mask her true SIR appearance. Mimi appears to be designed for observation and stealth operations. As seen in her first appearance as she slinks along the window sill of Ms. Bitter's classroom. She plainly stops in front of Dib and narrows her eyes, picking him up immediately as a potential threat to her mistress' mission. Unlike Gir, Mimi has brilliant red eyes and is far more directly obedient to her mistress.
Mimi has a rather large claw in place of a SIR's normal sized right hand. She uses this very effectively as an offensive tool. Her head lacks te SIR's usual antenna, rather, her head opens from the top, making her memory cartidges easy to access. In place of the Irken Armada symbol is Tak's personalized symbol, marking her as one of a kind, just like her mistress.
GENIUS!