Renesmee
A good friend of mine, yes. Witches were common in my world, I suppose more than others I've heard of.
I do not doubt that is true, but you also seem sensible enough to not wish to do damage to others, and find yourself on the wrong side of a hunter's wrath for it.
Take a portkey to [address], and tell the man at the desk that Mr. C wanted you sent up. He'll let you into the apartment. Don't hesitate to make yourself at home, either- the food, what little I have, is for the benefit of guests, anyhow.