You know, you'd be amazed how often I get asked that question.

[Well, really, if you're going to go around calling yourself 'the Doctor', you've got to be prepared for the inevitable 'Doctor Who?']

But it's just the Doctor. No other name, I'm afraid, or not one that matters. And you aren't the only one who deals with strange things. Haven't seen any creatures claiming to be demons in a few centuries, though.

[But it is strange that the demons are turning up at the same time as the Master again...]