This kind of cartoon kiss sound effect does not point to one clearly documented source and is better known as a stock comedy cue used across edits, animations and soundboards. Online, creators use it as a quick audio shorthand for a smooch, flirt, peck or exaggerated romantic gag. Its popularity comes from how instantly recognizable it is in very short clips, especially in memes and reaction videos where a single sound can turn a simple visual into a joke.