James doesn't answer at first.

Honestly, he's a little taken aback by the question.

Strange, too. Because no one's ever really thought to ask the Marauders why they call each other Moony, Wormtail, Padfoot and Prongs, and he never realized that until now.

"— it's nothing, really," he says, waving a hand.

He can't tell her the real truth. That would get into the how's and the why's and it's not his secret to tell.

"It's mostly to do with our Patronuses, you know? Mine's a stag."