It was a mugen prototype/concept.
It was present in the Japan Auto Show, but according to Mugen, it's just a prototype, unlikely to see the light of production.
I assume you saw photoes of it? Red, right? Rear door handles at the rear passenger window corners?
Notice that you won't find it in any other colour, because there's only ONE.. :P
That's as far as I know though, unless mugen decided to make it a kit..
The only Mugen version of the new civic is only in America in coupe form, the first civic to cost more than USD30,000. And it looks nothing like the Dominator.
The local one.. err.. I hesitate to call it a Mugen version since the wheels are 'Bleh!'.
If it does come out, the price will definitely a killer though, since mugen wheels are always very expensive..