Kirstee and Kaycee Tweevil, also known as the Tweevils, are the two secondary antagonists in the 2004 cartoon series Bratz.
Kirstee and Kaycee are two rich and rude teenage twins. They dislike their boss, Burdine Maxwell, though they often fear her wrath as well. The girls are also skilled experts at spying on their enemies and trying to steal ideas for Your Thing magazine.
As they are twins, Kirstee and Kaycee look almost exactly alike each other aside from some minor details. Both twins possess light skin, blue eyes, and light blonde hair. Their primary outfits include of a pink crown-shaped hair decoration holding up their hair in a bun, a pink dress, and tall pink wedge pumps. They can easily be told apart as Kaycee, the younger twin, is always wearing a white bandage on her nose.
Kirstee and Kaycee have known the four main Bratz girls since toddlerhood, and even back then they've been having a rivalry.
They tricked Jade into getting Burdine a cheeseburger for her lunch, causing Jade to get immediately fired from Your Thing. However, because of this, they indirectly caused Jade to open up rival magazine Bratz with her friends.
- Kirstee was voiced by Kaley Cuoco in season 1 and by Ashleigh Ball in season 2. Kaycee was voiced by Lacey Chabert in season 1 and by Kelly Sheridan in season 2.
- Kirstee loves ice cream as her favorite food, while Kaycee loves candy as well as ice cream.