Rex is adorable & good be a pedigree if he has no white markings at all & usually a big build to them,their called (Bombays) Just look up Bombay cats on your computer. The dandrif is waste from flea bites & is called dander. Looks like good old Rex needs a bath & treated for fleas. If you won't let you give him a bath ,like most kittys. Take a fine tooth comb for cats & comb his hair often,you can take a towel too & rough up his fur until the fleas fall off. Good luck