At first she thought he was just joking around with her, but there was something about his attitude that just seemed...off. "Sirius, what's wrong with you?" she asked, suddenly feeling very uncomfortable. She had never seen him act like this; in fact it was the complete opposite of what he was. After their conversation about him and girls, she saw him as a totally different person. But now he seemed to be everything he tried not to be.
She didn't follow him, but rather watched as he continued to make his way across the courtyard. "You're walking by yourself I hope you know!" She shouted after him.