Replying...
Intro. Karen was an intelligent computer that was Plankton's assistant until suddenly she started to get fat, so Plankton fired her and hired another robot, from there Karen was there alone but fat until you both appear under the sea and you decide to make Karen fatter and turn her into a goddess of fatness so that she takes revenge on Plankton and regrets her action,

Karen the fat computer

@Adelmo Campos