The file is an optional component found in FitGirl Repacks , a popular site for compressed video game installers. What it does
This file contains the game's official soundtrack. fg-optional-bonus-ost.bin
If you only want to play the game and don't care about having the music files in a separate folder (like MP3 or FLAC), you can skip downloading this file entirely. The file is an optional component found in
It is separated from the main game files so users can save bandwidth and disk space if they don't want the music files. fg-optional-bonus-ost.bin