Alternative Character Interpretation: It's possible that SpongeBob knew his bodyguard was the Strangler the whole time, and was messing with him on purpose. Note that when the two finally get home, SpongeBob accidentally calls his bodyguard "Strangler" before correcting himself. There's also the fact that SpongeBob set up the parties for right when he would be alone with the Strangler and pretended to be surprised, and how he doesn't show much concern when seemingly assuming Patrick was the Strangler.
The Strangler being excited to strangle SpongeBob to death at his house before laughing? All with dark music and a dark background? Disturbing. SpongeBob obliviously laughing along with him in the same way complete with the same pose? And still with the same dark music and background? Hilarious.
The Strangler getting SpongeBob's cleats stuck in his eye sockets is no doubt horrifying and painful, but his over-the-top screams of pain and the fact this all lasted for six hours makes the scene side-splitting, especially the Strangler's furious reaction to SpongeBob mentioning the Key Under the Doormat, making what he went through just to enter the pineapple house pointless.
Fridge Horror: When you think about it, SpongeBob's proposition of going to his house and turning off all the lights means he unknowingly let his assailant into his own home, removing his one and only place of complete privacy. Had he not been holding any parties that day, SpongeBob would be dead.
For Mr. Krabs, of all characters. When SpongeBob comes to him for help, Krabs is initially willing to help him, and doesn't ask for anything in return. For a character who only ever went one episode thus far without talking about money, that's huge. He becomes terrified when SpongeBob reveals who the bully is, but it's the thought that counts.
Among the people SpongeBob invited to his party are Squidward, Mrs. Puff and Plankton. None of them has their usual complaints for SpongeBob's and are genuinely enjoying themselves.
Catharsis Factor: Seeing SpongeBob and Patrick exposed as the "ghosts" to all of Bikini Bottom is very entertaining and quite therapeutic, especially if you were ever annoyed by their occasional Idiot Houdini moments.
Memetic Mutation: "And since when did I acquire all these portraits of [X]?"Explanation Sandy asking herself about suddenly having a collection of Patrick's portraits in her house. This is often used by media fans describing their sudden fixation on a given character.
Squick: At the prank shop, Patrick and SpongeBob are offered fake vomit, and then they are offered real vomit. Luckily, the duo take a pass on that one.
