So, is there anything you can safely use as a dye for your cat's fur?

We recommend:

OPAWZ Funky Pet Color Shampoo Ammonia Free and Paraben Free. Safe For All Pets That Can Be Bathed! The safe and gentle formula can be used directly to pets with white hair and very light color hair.
OPAWZ Semi-Permanent Dyes - Contains No Ammonia or PeroxideSafe and gentle semi-permanent colors for cats, gradually washes away in around 8 washes. Apply on clean and dry white or light color cat hair for best results.
Limited Offer: Cat-Safe Colors Value Pack

Please noted: You should never try to dye a cat’s fur who has any underlying health issues whatsoever, no matter what.