This sound comes from Undertale, the 2015 indie RPG created by Toby Fox, where character dialogue is often represented by distinct text sounds instead of full voice acting. Sans became one of the game's most recognizable characters, and his talk sound spread widely through meme edits, animation clips, and crossover posts. It remains popular because a few seconds of audio can instantly signal Undertale, a dry joke, or a smug reaction without needing a full quote from the game.