Two mainsails on a boat does not qualify as a unirig, any more than a sloop rig does. It's just two sails side by side instead of fore and aft.

In fact, I don't think unirig has anything to do with whether it is even attached to a mast. You could have a unirig that is jib only rather than main only. It's just about one sail, period, whateverwhichway you want to hang it up there.

In fact, if the only sail you have is a kitesail, I would guess that would also be a unirig.