If you are trying to open this file, you will need a utility like 7-Zip or WinZip to extract its contents and see the "story" inside.
A 7-Zip file containing a visual novel, a game's story assets, or a collection of digital stories. MAIS.7z
Wikipedia notes that 7-Zip is an open-source tool used for high-ratio file compression. If you are trying to open this file,
Files related to a specific community project or mod where "MAIS" is an acronym or title. Files related to a specific community project or
Can you provide about where you saw this name (e.g., a specific website, Discord server, or game modding forum)?
It is highly probable that this refers to one of the following:
The search results indicate that likely refers to a compressed archive file (with the .7z extension) named "MAIS." However, there is no widely known viral story, game, or cultural phenomenon specifically titled "MAIS.7z" in general public databases.