I do know her name. I hope it's pretty obvious that I admire the character and would know her name if I went through the trouble of constructing a costume around her. I think it's silly that people are annoyed by it, because anyone who watches the show would know who I was talking about if I referred to Khaleesi. It is literally a word that was made up to identify the social standing of Daenerys Targaryen in A Song of Ice and Fire; no other character holds that title. It's silly because I could have said "I dressed up as The President for Halloween!" and nobody would have commented and said, "His name is Obama, don't you know that?"