Harry Potter and the Half-Blood Prince
"Hi, Harry, I'm Romilda Vane," she said loudly and confidently. "Why don't you join us in our compartment? You don't have to sit with them," she added in a strange whisper, indicating Neville's bottom which was sticking out from under the seat again as he groped around for Trevor, and Luna, who was now wearing her free Spectrespecs, which gave her the look of a demented multicolored owl.
"They're friends of mine," said Harry coldly. (7.103-104)
It was a mark of the strength of their friendship that Ron did not laugh. (8.116)
Exactly what Hagrid would say when he realized his three favorite students had given up his subject, he did not like to think. (8.137)