Jeff the Killer began as an internet creepypasta character in the late 2000s, built around a haunting edited face and a story about a teenager who becomes a killer after a violent attack. The character spread through forums, fan art, readings and songs that retold the legend, including the creepypasta song this introduction is taken from. Short voice clips of the name became shorthand online for horror and jumpscares, which is why creators still drop this line into edits, streams and Halloween content today.