Quoted from the wiki.
A 10-hit combo, consisting of 5 swings doing 2 hits apiece, each followed by a phantasmal image of a golden Wolver that bites the area struck. The bite is roughly half the strength of the normal sword swing.
2 hits per swing as per standard, followed by a bite. does that mean that each swing hits 3 times (including the bite) for 15 hits total?
I'm not entirely sure, as I haven't had one myself, but I believe the phantom/hologram wolvers and their biting happens INSTEAD of the regular after-image cut, not in addition.
Also I've heard that they happen on a greater delay than the after-hits of all of the other swords in the series, and unless the monster is stationary or trapped in a corner or something you'll be pushing them away with each initial hit before the wolver-hits can actually land.
.. .. .. I'd use it anyways, though, simply because it sounds like the coolest -looking- weapon I've ever heard of. :P