The NPC joke comes from video games, where non-player characters repeat a small set of scripted lines with the same flat delivery every time you interact with them. Online, creators borrowed that idea to label real people acting robotic, repetitive or oddly scripted, and short voice clips became popular meme sounds for edits and reaction videos. This version packages that humour into a brief loop that can be dropped into gaming clips, live streams and social posts without needing any context, which is why it keeps being reused.