A gun.

“I suppose if I had to pick a weapon for self defense, the obvious choice is a gun. A shotgun or pistol I suppose. If you are talking weapons from here, I guess a strong sword, the one I have is pretty nice. Where did that sword come from anyway?”

“The last person I killed.” He answers in a matter of fact tone.

“Who was it?”

“Enough questions. You will know all you need to know soon enough.”

With that you are dismissed once again to the roof. The next morning as you join him he has two things for you. The first is a pair of basically skin tight black leather pants that lace up the front and end a bit below the knees. The second is a small hand crossbow, with a leg quiver that holds 10 bolts. As he hands them to you all he says is, “You need to cover that cock if you are going to pass as a human.” Plus as he hands you the crossbow he adds, “I couldn't find a gun.”

Another pair of months pass without so much as a conversation, there is only weapon training, eating, and sleeping. He trains you to use the crossbow in your off hand to keep people off guard, and to finish someone when they give you an opening. The training would work much better with more than one shot, you imagine, but still it seems to be an effective way of fighting. Of course you also notice he never attempts to block or even concern himself with your crossbow giving you the distinct feeling it isn't capable of hurting him.

Finally well into the next month you wake to him standing over you on the roof. “What is it? You never come up here.”

“Things have changed. Another is passing through the portal, you can't be here when they arrive.”

“Why?”

“You were right earlier. I am the last guardian, I trained you because I couldn't bring myself to kill someone that seemed so helpless. Now that another has arrived you must make a choice. You can challenge me for the treasure, or I can use a spell I know to blast you through a rift to another plain. I have no idea where you would go, it is random, but I wouldn't have to kill you.” He looks back over his shoulder, “Choose!” He yells at you finally.