Kai Green

From Ben10versepedia

Kai Green is the granddaughter of Wes Green who is a friend of Maxwell Tennyson and Max's former partner. She first made her appearance doing a dance. Kai was Benjamin Tennyson's first crush, but she was interested in him when he started transforming intoBenwolf even though she only wanted to "train and tame him". When Kai said this, Gwendolyn Tennyson gave her a firm talk after she admitted this. She makes her way into a second appearance during Ben's dream world in "Perfect Day".