Originally Posted by DiP

You don't need to have any Honor, and it doesn't "use" your Honor Virtue status for perfection. All you have to do is Honor your target, and it must be honored (i.e. if you can't honor it due to someone else already did or it has lost hit points, you can't gain perfection).

And yes, with 50 Bushido you can start using Honor to gain in perfection.