- Gary the Snail
- SpongeBob SquarePants
- Cowboy fish (cameo on TV)
- Incidental 107 (blue)
- Incidental 107's worm (cameo)
- Eugene H. Krabs
- Incidental 103
- Nudibranchs (debut)
- Puffy Fluffy (debut)
- Fortune teller (debut)
- Jellyfish (cameo in painting)
- Grandma SquarePants (mentioned)
- T.S. Halibut (debut) (mentioned)
The episode starts at SpongeBob's house, where he is feeding Gary. Afterwards, he has to leave for work, but Gary wants to go on a walk. SpongeBob tells him that he does not have time to give him one and sadly walks away to work, feeling remorseful that he had no time to hang out with Gary. As he goes to the Krusty Krab, he notices that Mr. Krabs refuses to give one customer service on account of him bringing his pet worm into the restaurant. This reminds SpongeBob of the fact that Gary is home alone with nobody to keep him company, prompting him to make a remorseful phone call reminding Gary that he will be home soon.
As SpongeBob gets off work at night, Mr. Krabs tells him that he needs help with loading coal out of the parking lot, but SpongeBob cannot help as he has to get back to Gary at home. Mr. Krabs lets him off the hook so long as he comes in work five hours earlier the following day to help with the parking lot. As SpongeBob is walking home, he notices a truck selling nudibranchs, which catch his attention due to their "cute" appearance. However, the lady selling them informs him of their danger (they are extremely vicious and hostile toward other pets, especially snails), but SpongeBob does not pay attention and simply runs off with a green nudibranch without paying for it. He buys this pet for Gary to have as his playmate while he is at work; he names it "Puffy Fluffy."
SpongeBob comes home and shows Gary his new playmate and places them next to one another to have them get along as he makes an enchiladas meal. Puffy makes blatant threats to Gary, but SpongeBob fails to notice the nudibranch's impending danger and instead accuses Gary of perpetrating violence against him or ignoring him. As punishment, Gary is put to sleep early tonight, next to Puffy Fluffy, then SpongeBob himself goes upstairs to sleep, berating Gary again when he disturbs him. Over the night, Puffy continues to threaten Gary as if he is going to kill him. Gary tries many defense mechanisms, but it turns out that Puffy Fluffy is stronger than him, making Gary more vulnerable to his abuse. They continue fighting throughout the night which eventually carries into the library, prompting a house fire made by Puffy Fluffy, who knocked over SpongeBob's fireplace.
The next day, SpongeBob wakes up to find that his house is a mess, and assumes that Gary caused it out of jealousy of his new "friend." He then walks into his exercise room to find Puffy Fluffy about to eat Gary alive, but, oblivious to the nudibranch's blatant abuse, once again accuses Gary of harassing him.
Puffy eventually traps SpongeBob as well, which gives Gary the idea to save him by getting out his lasso and freeing SpongeBob and intimidating Puffy, who runs off after Gary presents his defense. Despite this, SpongeBob still believes that Gary was responsible for Puffy Fluffy's violent behavior.
The episode ends with SpongeBob at work again, this time bringing Gary after the policy has been updated to allow animals in the restaurant so he won't be lonely anymore to his dismay. Mr. Krabs ironically hires Gary as the restaurant's second fry cook, as the episode ends.
- Puffy Fluffy attacking Gary when SpongeBob leaves the room.
- Whenever SpongeBob comes back, Puffy Fluffy reverts to his cute state, leaving Gary to take the blame.
- SpongeBob berating Gary for being mean to Puffy Fluffy or ignoring him.
- Gary using a lasso while wearing his cowboy hat.
|( ‣ ) Associated production music|
|( • ) Original music|
|( ◦ ) SpongeBob music|
• Clownfish Capers - Sage Guyton, Jeremy Wakefield [title card]
• Skipping to School - Sage Guyton, Jeremy Wakefield [opening]
• Grass Skirt Chase - Sage Guyton, Jeremy Wakefield [Gary grabs everything he needs to watch TV]
• Blazing Baloney Western - Nicolas Carr [Gary turns on the TV]
• Steel Licks 23 - Jeremy Wakefield ["Poor little snail, just wanted some fun time."]
• Blazing Baloney Western - Nicolas Carr [Gary watching TV]
• Happy Sack Shanty - Michael Bolger, Nicolas Carr [at the Krusty Krab]
• Steel Licks 3 - Jeremy Wakefield [no pet policy]
‣ Drama Link (d) - Hubert Clifford ["Eh?!"]
• Jovial Pirate's Jig - Michael Bolger, Nicolas Carr ["Hey, let's not be hasty."]
• Steel Licks 4 - Jeremy Wakefield [SpongeBob feels guilty]
• Blazing Baloney Western - Nicolas Carr [Gary still watching TV]
• Steel Licks 9 - Jeremy Wakefield ["Too distraught to even answer the phone."]
• Blazing Baloney Western - Nicolas Carr ["Hello. You've reached SpongeBob and...C'mon Gary"]
• Steel Licks 34 - Jeremy Wakefield [SpongeBob leaves a message]
• Steel Licks 35 - Jeremy Wakefield ["If we ever stop having so much fun, together!"]
• Blazing Baloney Western - Nicolas Carr [SpongeBob leaves a message]
• Steel Licks 26 - Jeremy Wakefield [SpongeBob puts the phone down]
• Slinky Panther Pants - Nicolas Carr [closing time]
• Salty Krab Jig - Michael Bolger, Nicolas Carr [Krabs re-tarring the parking lot]
• Steel Licks 20 - Jeremy Wakefield ["Poor Gary's been home alone all day."]
• The Pollywog Strut - Nicolas Carr, Barry Anthony ["Wow, Dad, is it really mine to keep?"]
‣ Why Am I So Poor? (b) - Niko Radic, Laszlo Borteri [SpongeBob buys another pet]
• Blazing Baloney Western - Nicolas Carr [Gary still watching TV]
• Silly Bob Conversation 2 - Nicolas Carr, Barry Anthony ["I brought you a surprise!"]
‣ Tales from the Swamp (c) - Ron Goodwin [Puffy Fluffy roars at Gary]
• Silly Bob Conversation 2 - Nicolas Carr, Barry Anthony ["Eat up, you two."]
‣ Jarabe Tapatio (a) - Gerhart Frei, Carlos Periguez ["I'm gonna make some enchiladas."]
• Horror House Of Wax Retro 2 - Nicolas Carr, Ron Wasserman [Puffy Fluffy eats the entire food bowl/Puffy Fluffy rips the squeaky carrot toy]
• Lap Steel - Nicolas Carr ["I hope you're happy now."]
‣ Finger of Fear - Fredric Bayco [Gary has to share his bed with Puffy Fluffy]
• Solo Steel 4 - Jeremy Wakefield [SpongeBob goes to bed]
‣ Drama Link (f) - Hubert Clifford [Gary enters]
‣ Music, Box - [General Series 6000 Extension] ["See? There he is, fast asleep."]
‣ Drama Link (c) - Hubert Clifford [balloon deflates]
‣ Cellar Search - Philippe Pares [Puffy Fluffy's grown to gigantic size]
• Horror House Of Wax Retro 2 - Nicolas Carr, Ron Wasserman [Puffy Fluffy roars at Gary]
‣ Lullaby Box - Johannes Brahms, Leo Nissim [SpongeBob talking in his sleep]
‣ Abject Terror - Paul Lewis [Puffy Fluffy chases Gary]
‣ Stealth by Night - Jack Coles ["Mmm, you're making meatballs, Grandma?"]
‣ Sword Fight - Harry Bluestone, Emil Cadkin [Gary putting out the fire]
• Vibe Q Sting - Nicolas Carr ["Huh?"]
‣ Alone in the Old House - Gregor F. Narholz [SpongeBob's library destroyed]
‣ Terror - Alan Braden [Gary's about to be eaten]
‣ Sword Fight - Sam Fonteyn [SpongeBob breaks down the door]
‣ Tales from the Swamp (a) - Ron Goodwin ["Gary!"]
• Horror House Of Wax Retro 2 - Nicolas Carr, Ron Wasserman [Puffy Fluffy tries to eat SpongeBob]
• Blazing Baloney Western - Nicolas Carr [Gary saves SpongeBob]
• Ad Lib Jig - Michael Bolger, Nicolas Carr [ending]
- This episode is available on the Heroes of Bikini Bottom, Complete Seventh Season, SpongeBob SquarePants Vol. 11, The SpongeBob SquarePants Collection, 3 DVD Value Pack, Snail's Meow, Spužva Bob Skockani DVD 4, Triple Pack 3, The Best of Bikini Bottom, The SpongeBob SquarePants 8 Season DVD Collection, Easter with SpongeBob, Kids Double Pack: Volume 3, Kids Double Pack: Volume 2, Next 100 Episodes, Big Hits: Volume 2, and The Best 200 Episodes Ever DVDs.
- The title card background for this episode is very similar to that of "Culture Shock." The only difference being that the title card for the latter is a lighter shade of red.
- It is also similar to the one for "SpongeBob SquarePants vs. The Big One," only that title card is blue and not red.
- This episode features a phone in SpongeBob's house that is not a shellphone. This phone was previously seen in "Procrastination."
- Incidental 41 is seen as a sheriff in the western crime movie or TV show that Gary is watching.
- Gary wears a soda drinking hat while watching TV. A soda drinking hat was previously seen as the main plot point of the episode "One Krabs Trash."
- In real life, nudibranchs (sea slugs) are worm-like creatures. However, in this episode, they are portrayed as fluffy fish until Puffy Fluffy turns into a vicious monster.
- Puffy Fluffy's species of nudibranchs is never referred to by name in this episode. It was only confirmed by source releases.
- It's revealed that Gary's first name is Garold.
- SpongeBob technically didn't have to get Gary a partner because he already has another pet called Shelley. She even appears during one scene of this episode. Specifically, when SpongeBob is sleeping in his bedroom and the ceiling cracks are falling off.
- This episode reveals that SpongeBob's garage is located behind the living room.
- Puffy Fluffy tries to eat SpongeBob during the climax of this episode. This makes sense, as in real life, nudibranchs eat sea sponges.
- This is the second episode where Gary wears a Krusty Krab employee hat, the first being "Banned in Bikini Bottom."
- There is an online game based on this episode called Gary's Revenge.
- In the German dub, this episode is called "Spielkamerad des Grauens," which translates to "Playmate of Horror."
- In the Polish dub, SpongeBob tells Puffy Fluffy to put Gary down, unlike in the original version, where it is the opposite.
- This episode was paired up with "Don't Look Now" during the Massive Monster Mayhem Marathon.
- The container for the chips that Gary eats is similar to the Pringles cans.
- Puffy Fluffy in harmless form looks similar to a piranha.
- Puffy Fluffy's multiple tongues inside of his mouth is a reference to the films Aliens and Tremors.
- T.S. Halibut is a reference to British essayist T. S. Eliot.
- When SpongeBob is walking away from his house near the start of the episode, his belt turns white for a split second.
- Throughout most of the western crime movie or TV show that Gary is watching, the cowboy fish is in his normal olive green design, but in the last scene that is shown, he is instead purple with a blue fin.
- When SpongeBob carries a food bowl into the living room, the inside of his mouth appears yellow instead of red for a split second.
- When Puffy Fluffy is rummaging through SpongeBob's fridge, there are only two frying pans on the rack near the stove. However, when Gary climbs onto the stove in an attempt to defend himself, there are now three frying pans that were not visible in the aforementioned shot.
- Mr. Krabs tells SpongeBob to come in five hours early at work, so he should have woken up at 4 a.m. instead of 9 a.m.
- In this episode, SpongeBob's exercise room is seen to be on the first floor below the library, when in most other appearances, it is on the second floor, with the library next to it.
- When SpongeBob says, "This is exactly what I was talking about--," some of Puffy Fluffy's teeth is colored red instead of white.
- Squidward's and Patrick's houses are missing from the scene where Puffy Fluffy runs away from SpongeBob's house.
- In "Grooming Gary," SpongeBob says he understands snail language, but he does not use said skills when Puffy Fluffy is present.