Rochelle usually is the one to take Frido, the class pet, home with her during the weekend, but she has the Gargoylympics to go to this particular weekend. As such, she's looking for someone who can take care of him this time. Draculaura wonders aloud who would say no to "such a luxurious coat", which Cleo overhears. She immediately volunteers, thinking she'll get a coat, but doesn't back out when that turns out not to be the case. Rochelle instructs her to abide by three rules: never give Frido cheese to eat, keep him warm, and never let him near electricity. Cleo is a little overwhelmed, but her friends offer to assist her.
At Cleo's house, Draculaura and Frankie are enjoying a cheese table when Frido comes begging for treats. Frankie warns Draculaura not to give him cheese, but Frido proves the kind of pet that just takes what it wants. Assuming he's thirsty, Abbey gives him a bowl of water, which is frozen by her powers. Lagoona tries to call her back, but Frido has already taken a sip and is feeling the effects. Frankie tries to wrap a blanket around him to get him warm again, but Frido tackles her, provoking a charge from her.
With all three rules broken, Frido gets hyperactive. Cleo gets a call from Rochelle, whom she lies to that everything is going well. To her horror, Rochelle announces she'll come get Frido in a moment. The girls quickly run after him, only to find him in the middle of the living room as a skeleton motionless lying among his shedded fur. As the girls are mourning, Rochelle steps into the room. They try to apologize and console her for the loss of Frido, but she cheerfully replies he isn't dead; he's in hibernation. Breaking the rules made his start a week early on his yearly schedule. The girls, Draculaura in particular, are relieved.
- In the title, "pest sitter" is a pun on "pet-sitter" and "pest".
- The three rules of taking care of Frido echo the three rules of taking care of a mogwai in the 1984 horror comedy movie Gremlins.
- This is one of the three webisodes first released as an extra on the "13 Wishes" DVD on October 8, 2013. As its "Ghouls Rule"-predecessors, it will likely be released in the regular line-up some months into 2014.