Peanut Butter is a recommended character who was recommended by simondomino in Episode 13. Peanut Butter is a limbless brown blob of peanut butter. In Episode 13, Peanut Butter was seen next to Phone when Eraser is looking for a ball. Firey also mentioned Peanut Butter before in episode 12, when he tasted something like peanut better.
Peanut might be friends with Peanut Butter because the latter is made out of peanuts.