Most of Mimi's history is unknown, but according to Dexter Mimi is a telepath that can predict the crimes of supernatural villains. In order to protect Mimi from danger both mentally and physically he built a machine called the nephilm. Unfortunately not only does the nephilm cease all Mimi's motor functions, but should she leave the nephilim's range she would be defenseless. On her ninth birthday Mimi's nanny Jeff the Spider had prepared all of her favorite foods, but Mimi wasn't truly satisfied and wanted her mother to come who was off on a mission. When Mimi wouldn't stop calling out to her mother, Raven told Mimi to stop whining implying that Blossom was busy keeping the world safe which implied Blossom was keeping her safe. Although Mimi has stopped crying she started a food fight with Raven. After the food fight Jeff had asked Raven for a favor to give Mimi a bath which she agreed to because Jeff asked. During the bath Raven admitted the both of them made a mess and knew Jeff was always the one to clean messes afterwards. Raven wanted to give Mimi a present for her birthday and Mimi wanted a chakra gem Raven promised to give her a chakra gem for her next birth day and the two shared a bond.
The War of Megaville Aftermath
In the Aftermath of the war in Megaville, Mimi is all alone in the wreckage. Luckily Jeff finds her and warns her it isn't safe there. Then a giant lava monster rises from the ground and attempts to attack the two, but Raven, Irwin and Hoss Delgado help and keeps the lava monster from taking jeff and Mimi. Raven tried to teleport Jeff and Mimi away, but HIM slashed Raven in the back and snapped Irwin's neck. The lava Monster takes Mimi and tries to take her, but Raven hits the Lava Monster with a meteor and Blossom kills the Lava Monster afterwards. While Blossom kept Mimi from harm, Raven gave Jeff a golden necklace she intended to give Mimi. Both Hoss and Raven restrain HIM from attacking Mimi and start their plan to kill HIM with a nuclear bomb. Even though Raven and Hoss gave their lives for Mimi HIM had survived the explosion and reappeared in his giant form. After taking Mimi HIM first had Mimi kill Blossom. To make Mimi resemble HIM more he cut off her hands, replaced them with claws and exposed her to every evil possible and becoming Her.