firecat

I adore tuxedo cats! He's a fine looking example.

I second what everyone else has said about taking it slowly, keeping them separated initially and slowly introducing them (over a period of days/weeks) with supervision. Also, don't expect 'em to be buddies immediately. I've introduced lots of cats to my household this way over the years, and I've found that generally it takes weeks to a couple of months for the cats to really start getting comfy with each other, by and large. If more than a few months have gone by and they're still fighting aggressively (other than the random thumps and hisses that are part of regular cat dominance negotiations or grumpiness) then you may have a compatibility problem; but I wouldn't worry too much until then. Good luck!