1: Katana is Japanese for Sword. That was an ďincase you couldnít tellĒ little thing.
2: Wow. I added Totosai in here! But he died really quickly. Why? I donít know. I just needed Inu to get the Tetsusaiga. Ok, I have a reason, but they wont know it. He was an important asset to Youkaibo, so if he leaves the place, there's like a tracker that kills them after a while...so, there we go. Totosaiís death.
3. The Engraving comment. Youkaibo sucks. Sometimes demons are supposed to have markings, but they donít show up until later, so the scientists cut it out so itís more of a scar than a marking. Bastards, huh?