It is unknown when Francis bought Pickles, but she quickly developed a habit of marking her territory. She also fell in love with Spitsy, though when and how they came together is unclear. Once, Nate got a black eye trying to stop Spitsy from reaching Pickles while they were on a walk together. She is a smart cat that has completed her EMT training, and can mountain bike and juggle on a unicycle while whistling. Once Francis brought her to his basketball game so she could be their mascot, even giving her a miniature jersey and tiny pom poms, which Nate didn't like, leading to him deliberately throwing a basketball at her.
Pickles is shown to be an outdoor cat, always laying on the ground, as Nate says, as if she owns the world. Pickles is an example on a list on why Spitsy is not a normal dog. Pickles and Spitsy seem to enjoy spending time together, including playdates and Pickles' birthday.
Francis is Pickles' owner. Francis loves her, and has taught her lots of tricks.
Essentially, Spitsy is Pickles' soulmate.
Pickles does not seem to care about Nate. On the other hand, and partially due to Nate's fear of cats, Nate deeply hates Pickles, also describing her as obnoxious. Once, he got a black eye trying to stop Spitsy from reaching her while they were on a walk together.
Behind the Scenes
Pickles and Spitsy are the only animals in the Big Nate series that make more than one appearance. Even though "Pickles" is considered a boy's name, she is a girl.