Mimi is a major character in Super Paper Mario. She is a shapeshifter who usually takes the form of a little girl. Her true form is a strange spider-like creature. She is one of Count Bleck's major minions along with O'Chunks, Dimentio, and Mr. L. The party first encounters Mimi in Chapter 2 where she pretends to be a maid at Merlee's Mansion and makes them pay a million rubees for a vase that the party must break to advance in the story. After paying off the debt and moving on to the Mansion's basement, she mimics Merlee and the player must enter a gameshow hosted by The Interned in which the player has to ask the real and fake Merlee's questions to determine who is the impostor, although the real Merlee has a fly floating around her head because she was hiding in a toilet. Mimi reveals her true form when the real Merlee is chosen and attacks while Merlee cheers on Mario to destroy Mimi's invincibility barrier. Later at Sammer's Kingdom, she stalls the party so that the void will be able to destroy the world. At Count Bleck's Castle, Peach saves her after she is defeated, temporarily removing her from the party.
After you beat the game, Mimi will again appear as a maid in Merlee's Mansion, but she claims to actually be hired as one (although she still never removed the traps).