Unknown weapon?

So I was in the Depths on my SL1 character, and for the first time I noticed the butchers carry a weapon in their left hand. A couple hits later, and I got snagged by it. It pulled me to the ground and the butcher smashed the blade into my back.

After reviving and sprinting back I looked a bit closer. It looks like a wooden hook, something I'd never seen before. In my experience every single weapon an enemy uses, barring the boulder giants, can be obtained. Maybe a rare butcher drop? It's not part of the Knight's Honor.

Anyone know anything about it? Am I just overlooking something? Anyone asked this before?