"A what?" shouted Ginny, drawing her wand. "A what, exactly?"
"He doesn't mean anything, Ginny -" said Harry automatically, though the monster was roaring its approval of Ron's words.
"Oh yes he does!" she said, flaring up at Harry. "Just because he's never snogged anyone in his life, just because the best kiss he's ever had is from our Auntie Muriel -"
"Shut your mouth!" bellowed Ron, bypassing red and turning maroon.
"No, I will not!" yelled Ginny, beside herself. "I've seen you with Phlegm, hoping she'll kiss you on the cheek every time you see her, it's pathetic! If you went out and got a bit of snogging done yourself you wouldn't mind so much that everyone else does it!"
Ron had pulled out his wand too; Harry stepped swiftly between them.
"You don't know what you're talking about!" Ron roared, trying to get a clear shot at Ginny around Harry, who was now standing in front of her with his arms outstreched. "Just because I don't do it in public -!"
Ginny screamed with derisive laughter, trying to push Harry out of the way.

Harry Potter and the Half-Blood Prince
Chapter 14, Felix Felicis
by J.K. Rowling