She would be brief, since Hogwarts had rules apparently about students lingering at the staff dais too long, but Louise deemed it perfectly necessary. In theory, she was technically not a student anymore, but a graduate. Yet she didn't need her diploma withheld for any reason. Smiling politely at the staff members she passed, including the Williams siblings, who were tough, but definitely educated her well enough she didn't stop however until she was in front of the librarian.

"Sorry for not getting these back to you sooner," Louise said, removing the couple books from her bag. In the top book, was a parchment hidden between the cover and first page with her contact information on it. While it couldn't be certain that he would find it, if he was the dutifully librarian she thought him to be, he would likely inspect the books before re-shelving them.

"Thank you," she muttered, sliding them toward him, which was an all-encompassing thank you. For the books and advice, but also being a sound listening ear on the cruise, and of course, for being him. She wouldn't keep him from continuing his feast though. After a brief moment of locking her eyes on his, she turned to head back toward the student tables. The ball completely in his court now.