She is a goth girl, she has dyed black hair with blue and red ponytails, and always wear dark clothes.
She can be mean, but deep down, she's a nice girl, just don't mess with her, or she'll make you pay, she is also determined and brilliant, she loves Edgar Allen Poe, and she and Sean used great teamwork to defeat The Evil Thing.
- Max Keller is her little brother, who she loves, but pulls pranks on him all the time.
- Sean is a boy at school that she crushes on in the beginning, by the end, they became really good friends. (It's unknown if they actually have a romantic relationship later on)
- Priscilla Wright is a mean girl at school, and she picks on Cassie, so in revenge, she put cockroaches in the pumpkin pinata, and Priscilla got covered in them and landed in the cake.
- The Evil Thing is a monstrous creature that tried to feed her brother to it's infants.