Why did I choose that nick?
Let's start with the meaning of the word. Coven is
A group of witches, or a meeting of witches.
I guess this didn't explain the reason... Even made it more mysterious... (About what I wanted, hehe) So now I'll tell you: I just love Mercyful Fate and King Diamond, and as everything that has something to do with them is called Coven...
Oh, and of course I just love to confuse people ;^).