If you're looking to put together or manage a save file for "Tsukihime," here are some general steps you might follow. Note that specific steps can vary depending on the version of the game you're playing (e.g., original release, remake, or a fan patch) and the platform (PC, console, etc.).
Data is stored in your browser's local storage . Tsukihime Remake (2021) : tsukihime save file
Ensure your antivirus is not restricting the game from writing files to the Documents folder. If you're looking to put together or manage
C:\Users\[Username]\AppData\Local\VirtualStore\Program Files (x86)\Tsukihime . tsukihime save file