Mary Katherine, who prefers to be called "M.K.", is a 17-year-old, who had issues dealing with her father due to the fact that he was obsessed with his work. Additionally her mother, his wife, recently died, placing her under a lot of emotional stress. She moved in with her father because she promised her mother she'd try to repair their relationship, which fell apart because of his obsession with the leafmen. After their adventure in the forest she became more open having found what he had discovered about the Leafmen was true. She plans her sense of adventurous and bravery over the course of the adventure. She has a love interest in Nod and in the end shared a kiss with him. They still maintain connection, although the view of their relationship with their natural size differences remains unclear other than friends. MK is smart, pretty, feisty, witty, loving, and independent.