April O'Neil (2003)

April O'Neil is a 23-year-old scientist working as an assistant to Dr. Baxter Stockman at a New York laboratory. However, when she discovers her boss is involved in dangerous experiments and finds herself being pursued by robots called Mousers, the Teenage Mutant Ninja Turtles help her escape. From that moment on, April develops a close friendship with Leonardo, Raphael, Donatello, and Michelangelo, who become like family to her. After leaving her job at the lab, she opens her own antique shop called Second Time Around, where she sells vintage items and finds a new way to make a living. Throughout the series, she helps the Turtles with her scientific knowledge, intelligence, and courage, learning to defend herself and actively participating in their adventures. She also develops a romantic relationship with Casey Jones, with whom she shares numerous experiences, arguments, and special moments.

Hair: red, usually tied up in a bun.
Eyes: green.
Skin: fair.
Body type: slender; over time demonstrates greater physical ability.
Usual clothing: short-sleeved purple crop top, loose khaki pants, dark belt and dark blue shoes.
General style: informal, practical and simple.

April has a fairly balanced personality: she is kind, but that doesn't mean she lets others decide for her.
Intelligent: has scientific knowledge, knows how to investigate and understands complex situations.
Independent: is able to make decisions on their own and build their own life.
Brave: although at first he is frightened by extraordinary situations, he learns to face them.
Protector: She cares a lot about Leonardo, Raphael, Donatello and Michelangelo.
Patient: usually tolerates the Turtles' antics, even when they complicate things.
Astute: She uses her knowledge and observation skills to find solutions.
Loyal: does not easily abandon the people he loves.
Practical and sensible: she usually brings a more rational point of view when her friends are carried away by their emotions.