Prin, I don't think the colour makes a difference, I have 2 black and 2 black and white cats, so I bought a very very dark green couch.......and there are goober marks EVERYWHERE!! (looks like the trails snails/slugs leave behind)....
So I am forever washing up slobber marks! (and yes all my cats slobber when they sleep......didn't know that until I bought the dark green couch though
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