She is approximately the same height as Karin and has black hair.
She is shy and somewhat intimidated by Karin, as she constantly does what Karin tells her to do.
Agent of the Shinigami arc
During school, Midoriko goes to the bathroom and hears Karin Kurosaki yelling at Yuzu Kurosaki. She goes up to Yuzu and asks her how Karin's doing, but then retracts her statement, claiming that she already knows the answer. They then notice that Karin has stopped yelling, and Karin leaves the bathroom stall she was hiding in. She yells at Yuzu to get her stuff from the classroom as she wants to leave early today. Karin then asks Midoriko what she's doing here and then tells her to go as well. As Midoriko leaves, she wonders why Karin is in such a bad mood.
Later, Midoriko spots Kon (in Ichigo Kurosaki's body), jumping on top of the school walls. She is shocked by this, and Karin immediately begins threatening her, convincing her that she didn't see anything.
- Bleach manga; Chapter 8, page 6
- Bleach manga; Chapter 8, pages 7-9
- Bleach manga; Chapter 15, page 16