Dorian's silver-green eyes shift around the Tavern a moment to make sure that no one is listening in on them or watching them. It's not as if he doesn't just scream Tevinter Mage on his own. Staves usually meant magic was sure to follow. He clears his throat and tries to think of a layman's way to describe things. If he ever doubted (and he didn't) that the other man was from another world, he certainly knew for certain now.

"Right, uhm, well, mages draw their power from what we call the Fade, which is a spiritual realm parallel to our own. It's where spirits and demons reside. Which is why it makes things a little more dangerous for those of us with magic. And you should be made aware that with the use of magic comes the potential for possession from a demon. So if you start having dreams of speaking to one, always say No. There's usually a catch and they will almost always end up turning you into an abomination."