She is a grade 1 jujutsu sorcerer who works independently and only in exchange for money. She is also the older sister of Ui Ui and was a senpai of Satoru Gojo and Suguru Geto during their time at Tokyo Jujutsu High.

Species: Human

Gender: Female

Hair Color: Pale Blue

Eye Color: Lilac

Relatives: Ui Ui (Younger Brother)

Occupation: Jujutsu Sorcerer

Grade: Grade 1

Appearance: Mei Mei is a young woman with light peach skin and small, sharp dark brown eyes (dark purple in the anime) with thin eyebrows. She has long blue-tinted silver hair normally styled into two braids, one that covers her face and the other hangs behind her head down past her shoulders. This appears to be her preferred style while working as a sorcerer. While relaxing or casually playing ping pong, she'll let her hair down or style it into a single braid.

As a jujutsu sorcerer, Mei Mei sports a dark bodysuit with a skirt attached. There are also pants underneath that cover her legs and tuck into boots of the same color. (In the anime, Mei Mei's suit is purple and her boots are light brown). In 2006, Mei Mei wore a suit and tie with her hair kept in a high ponytail and two parallel bangs that left her face completely unobscured.

Personality: Mei Mei is a very calm and relaxed woman who can keep her cool in any situation. While very kind and honest, Mei Mei is very open about being greedy. Monetary value is the most important thing and quite possibly might be the only important thing to her. She considers herself to always be on the side of money and doesn't get out of bed for free. Allegiances and politics don't matter to Mei Mei as long as she gets paid for being a sorcerer. She also claims to not understand relationships not based on money.

Mei Mei believes that anyone else's life's value is proportional to how useful they are to her. "Service potential", a concept not supposed to be applicable to humans, is life itself for Mei Mei. She stated to a defeated curse user that she beat him because he was a murderer who took lives but didn't understand their value. In her eyes, Niji Ebina had no service potential, so Mei Mei didn't hesitate to kill him.

Despite her very questionable morals, Mei Mei maintains a relatively friendly demeanor at all times. She is interested in the potential and abilities of her allies, often recognizing their growth and commending them. Mei Mei is one of the people in agreement that Maki Zenin should have been long promoted from grade 4. She also recognized that Yuji was exceptionally strong without an innate technique and compared him to Atsuya Kusakabe. Mei Mei is fond of Kusakabe, expressing respect for him both as a sorcerer and an individual. As a sorcerer, Mei Mei compares him to a swiss army knife superior to herself and all others ranked grade 1. As a person, Mei Mei believes he is kindhearted to his core.

Outside of money, Mei Mei cares most for her younger brother Ui Ui, with a disturbingly close relationship. She often praises and rewards him for doing well, whether it be working for herself or others. When the clan head of the New Shadow Style school threatened Ui Ui's future, she took that as a personal front and assassinated them to protect him.

Skills/Abilities: Master Armed Combatant Great Tactical Intellect Cursed Energy Reinforcement Cursed Technique; Black Bird Manipulation: •Bird Strike

Equipment: Battle Axe: Mei Mei's primary weapon in combat is her large, light-colored two-handed axe cursed tool. The head of the axe is engraved with a symbol and the lower handle is wrapped in cloth. The axe itself is almost as tall as Mei Mei is and she keeps it inside a carrying case or makes Ui Ui hold it when she's not using it.