In the beginning of Episode 2 (The Brown Sugar Outlaw) 12 years ago, it shows Michiko in Vermelha in a prison van being driven to Diamandra prison for charges of destroying numerous properties related to the criminal syndicate Fantasma
In Episode 5 (The Idiots' Saudade, Part 1), Michiko is shown again in Vermelha 12 years looking for Cryil, the leader of Fantasma. She wants him to give back all the Monstro members, she is not a member but just wants them back. However, she is beat up by the members and is forced to leave in "four seconds" or he will shoot her.
In Episode 6 (The Idiots' Saudade, Part 2), She is shown as a young girl along with Atsuko trying to steal a money box from the "orphanage" she lives in. She is mad at Seria, who runs the orphanage, because she just sells and buys kids, one of them being a friend named Yolanda. Seria says she is in a nice place but Michiko knows it's a lie.
Michiko's relationship with Hatchin was rather complicated at first, due to their clashing personalities. But in time the two drew closer to one-another in their adventures In episode 22, when Michiko left Hana in Hiroshi's custody and declared that she was going to return to jail to serve out the rest of her sentence, Hana was deeply saddened that they had to part ways. Years later, after receiving various gifts of lingerie for weeks, a determined Hana used a large map to pinpoint and travel to the location where Michiko would show up, the two were able to ultimately reunite while embracing one another.
Michiko first meets Hiroshi as a young woman in a house where a person named Sascha may live as a hide out. Hiroshi and another person bust open the door with guns and masks on. only to walk in on a topless Michiko. Hiroshi, feeling bad tells her to put on the shirt hanging on a line next to her, but she says it's not dry. Hiroshi then takes of the mask that is a sheet and throws it to her. Instead of putting it on she walks over and headbutts him. The other man runs away due to the fact that the guns were not loaded. While Hiroshi is down with his nose bleeding, she loads the gun he dropped, she doesn't fire but instead wipes the blood off. This may be where they "fall in love".
Prior to the show's main plot, Michiko used to hang with Atsuko when the two were younger. Both were raised by Seria in an orphanage, with nothing being known or shown about their origins before then. Michiko tended to be more of a troublemaker, and from this Atsuko did not want to end up like her. Despite this, Atsuko still had a fondness for her.
From the start of the show, Atsuko is in charge of tracking down and arresting Michiko after she breaks out of prison. She ends up chasing her and Hatchin all across The pair have a form of rivalry, however Atsuko still does a few things that imply she is looking out for Michiko's well-being. Examples include letting her live after confronting her at gunpoint and seeing her try to shoot an empty gun (The Carnival of Hyenas), trying to talk Michiko out of chasing Hiroshi (Nettlesome Light-Blocking Butterfly) and making a deal to let Hatchin be with her father in exchange for turning herself in (Run As You Are).
"Hey, get on with it! Otherwise I will shoot you in the head, and your brains will go flying!"
"Is it you, Hana?"
"I'll send you on an express train to hell."
"What's up with your tits?! They don't jiggle at all!"
- The name Michiko means "beautiful" (mi), "wisdom, intellect" (chi) and "child" (ko).