Cassie Knisley

“Hmm,” said a small voice in his ear. “Difficult. Very difficult. Plenty of courage, I see. Not a bad mind either. There’s talent, oh my goodness, yes — and a nice thirst to prove yourself, now that’s interesting. . . . So where shall I put you?”
Harry gripped the edges of the stool and thought, Not Slytherin, not Slytherin.
“Not Slytherin, eh?” said the small voice. “Are you sure? You could be great, you know, it’s all here in your head, and Slytherin will help you on the way to greatness, no doubt about that — no? Well, if you’re sure — better be GRYFFINDOR!”
― J.K. Rowling, Harry Potter and the Sorcerer's Stone