Using the format [Funny Description]: [Filename].mp4 is a common way to label "shitpost" or meme content, making it look like a leaked or raw file discovered on the internet.
While the exact .mp4 filename you mentioned is a specific variation, it aligns with several viral trends: 3 rude 12yo girls show.mp4
The most famous version of this "useful feature" trope is the "Plash Speed" video, where a husband tries to trick his wife into believing a new PlayStation is a high-speed Wi-Fi router. Identifying the Video Using the format [Funny Description]: [Filename]