Knife has an extremely destructive and malicious attitude, being much of a bully to victims such as Paper and Marshmallow in particular. He has shown to be lazy in "A Lemony Lesson" where he told Paper they didn't need to compete. He has the ability to cut into things due to his sharp physical nature. However, he was shown to have a soft side in spite of being so traitorous and mean, as he likes the television show Desperate Housewives and Dora Dolls. 