Wikipedia
Karai is a fictional character in various installments of the Teenage Mutant Ninja Turtles (TMNT) comics and related media, where she is usually a high-rank member of the Foot Clan outlaw ninja organization. She was originally introduced in Kevin Eastman and Peter Laird's comic book series Teenage Mutant Ninja Turtles in 1992. Since then, she has appeared in several different TMNT comics, cartoons and films, as well as in about a dozen video games (including as a playable character in Tournament Fighters, Battle Nexus and Smash-Up).
In some incarnations of the character (including the 2003 cartoon, the 2012 cartoon, and the 2010s comics), she is closely related to the villain Shredder as his adopted daughter or biological granddaughter. However, in her original comic incarnation, Karai was completely unrelated to the Shredder and was actually higher in the Foot Clan's global hierarchy. In most works, she shares a particular rivalry and love-hate relationship with the Turtle leader, Leonardo. In the animated and game adaptations, Karai is primarily voiced by Karen Neil, Zhang Ziyi and Kelly Hu, while Minae Noji and Brittany Ishibashi portray the character in live-action films.