If you meant to remove the trailing dots or add a file extension (like .mp4 or .avi ), that would depend on the original file. The "REM" might be part of the scene title, a release group tag, or an abbreviation for "Remastered" / "Remux".
The text you likely want to extract or correct would be: MySistersHotFriend.19.05.07.Victoria.Lawson.REM...
It looks like you're referencing a filename pattern typical of adult content releases (often following a format). If you meant to remove the trailing dots
Could you clarify what you need the final text for — renaming, searching, or labeling? a release group tag