actually, the sword bec noir has isn't a katana, as a katana has a curved blade. it's either a chokuto or a ninjato, but hard to tell since there are no pictures of a real sword. the better guess would be chokuto, since that's the blade depth from what i can see.

All I know is that the sword that Dave killed the crow with is a katana so that’s what’s in Bec Noir’s stomach.  If he picked up a different sword along the way then so be it but I don’t recall that taking place. If it did feel free to correct me.