L'Hermione ou l'Emma.

"Here's my costume for Harry Potter night. I'm going as Hermione."

"Now, are you going as Hermione or the actress who plays Hermione?"

"Hermione."

"OK, but are you going as Hermione or Emma?"

"Hermione."

"OK, but it looks like you may be going as Emma Watson, the actress who plays Hermione."

"Hermione."

"OK, but do you have robes?"

"Hermione."