Not much is known about these two, other then them being twins, and being the third and fourth children of Maria and Keswick.
Kassie is the older twin. Her favorite color is crimson-red and dark tan. Her hair is very short and usually has a small, purple clip holding it together. Kassie is just like her mother; violent, rude, and destructive (which is why she's holding a gun in the image above). Kassie's bangs also hide half of her face, because she is NOT sociable with other people.
Kessie is the younger twin. Her favorite color is purple/violet/indigo and dark navy/cerulean/azure blue.