Do you use steam version? Right click game, open properties, look for option that is something like starting parameters (I don't remember the exact name atm and can't open steam) and add "-blood 0 -bloodstains 0" to it.
Non steam: make a shortcut to your toribash.exe, edit its properties, add "-blood 0 -bloodstains 0" at the end of the path (something like "C:\my games\tb\toribash.exe -blood 0 -bloodstains 0" and use the shortcut to play.