Kate

A model and up-and-coming movie star, she transforms into the yellow bunny Dopamine using an earing and a compact. She is often "busy" with other jobs and tends to speak in a monotonous tone. When she transforms, she says "Appear, Dopamine!" She is the black-haired girl and is a strange character who is into the occult. She owns a crystal ball and makes tea using a chemistry set. Dopamine is a chemical in the brain which affects adrenalin and the functions of memory, attention, and problem-solving.
-bio taken from Wikipedia