Sorry to hear it. Usually this is caused by antivirus software removing some core files required by the game engine.
Try this:
- Disable your antivirus temporarily - usually a right click menu from the system tray
- Extract the zip file again
- Run the file "Monster Girl Tailes 64-bit.exe"
NOTE: Don't forge to re-enable your antivirus software afterwards.
It may also be your zip software. Using something free like WinRAR or 7-zip should be fine.
Sometimes the inbuilt Windows extracter doesn't work so well.
Kind regards,
iLEWD