Five Week at Nomok's is a fan-made horror game in the style of Five Nights at Freddy's, and this clip is one of its jumpscare sounds, the short burst used when a character suddenly appears. Sounds from fan horror games often travel beyond their original game through soundboards and short videos, where they are reused as generic scare effects even by people who have never played the title. That second life explains its continued use: the burst is instantly recognisable as a jumpscare, needs no context to work, and fits easily into edits, streams and reaction clips.