Well, upon your description. There is a broad number of people you could be. Although the more I think about it, exactly how many members would have used the term "moniker"? Not many, unless someone learned some new words. The "Maybe even a clan leader." bit isn't much of a clue. Also, how many guesses does one get?
I wanna say Asto based on the whole "moniker" idea of mine. But there are quite a few other names I could pitch out as well.
Could you give another clue?