"Homie" is a black American Shorthair; a recent adoptee from a friend's move
into a new, more-desirable, but non-cat apartment.  Watching  Middy-Boo, who
is my first-adopted blackie of two years and Homie discover that neither was
the only black kitty in their respective worlds any more was an experience
unto itself; they of course started off hissing and skittering, but now they
all but dance together in remarkable harmony when their paths cross on the 5k
s/f terazzo floor that is their mousing ground.  (I look after a commercial
building; these two are on deck for Rodent Control Duty.)  It's overkill, but
not lonely for either one any more.

That "cats-first" phase of Homie's intro to the House took about five days.
Now that Homie has settled in to his new life with a cat-friend, he is coming
around to YT for attention more and more often as well.  And that is where
this particular cat's personal oddity has plainly evidenced itself.  Catch
this:

At first, Homie's "affection-seeking" behavior seemed oddly ambivalent - to-
antagonistic.  I would openhandedly stroke-pet him as apparently requested,
only to receive a hiss and a bolting-away as the response.  But he kept
coming back for another try, and a couple of days back I finally caught
Homie's point:  Petting annoys him - especially down his neck and body mass.
Grab-stroking his tail in passing is OK - but /knuckling his head/ gives him
consistent, drawn-out enjoyment!

I call; Homie comes.  "Hey, ya want I should knuckle your head?" I asks,
proffering a bent-fingers hand-end.  "Yah, yah, yah, yah!  Knuckle my head a
LOT an' do it NOW!" comes his consistent body-language response as he butts,
digs and grinds his coal-black forehead into my waiting knuckles with a
surprisingly consistent circular sort of head motion.  Although a minute or
less of ordinary petting (the kind that Middy-Boo soaks up with big purrs for
twenty minutes at a stretch when available) sends him bolting off with a
hiss, knuckling his head in this manner is sheer joy for him.  He will break
away from the food dish for a knuckle-job.   He goes after my knuckling-hand
for more high-intensity knuckling straightaway if I withdraw it before he is
satisfied.

One shade of black, to be sure.  Two very different cats, no mistake.  Go
figure!  ;-)  Wotta spreaduvva luv-spectrum.  Just like hoomuns.