Kylose is an experimental Irken created by Invader Kai. She was created to help Zim and Kai. During one of Dib's attempts to expose Zim, Kylose was accidentally attached to a machine which mutated her. She was then blinded by greed and taken over by Dusq. She tried to kill Zim 3 times when she was mutated. She eventually went over-powered and tried to destroy Earth. Luckily, before she could, Zim and Kai defeated her by singing a lullaby which Kai used to sing to her.
As a non-mutant, she was very sweet and kind like Kai. When mutated, she became similar in personality to Giygas. She is now evil.
As a non-mutant, she looked like Kai, only with light blue eyes. When mutated, her limbs became tentacles, the spots on her PAK became tentacles, her eyes turned black, her antennae became crippled, and her uniform became purple.