FTW you guys are noobs, HOJO did the Tatoos on Red XIII, not this

Its probably the norm for Red's species to have tatooes at an early age. Isn't Red only 15 or 16 by human years in the game? He had tatooes, then.
Or this, (though it is true, Tatoos dont magically apear, unless they too were cloned, hmm...)

Simple - he's not the last of his kind.
CHOCOBO KEV is right on Red XIII.