Prompt: (dialogue) "Haven't you heard of peace on earth and goodwill towards men?"/"No."
Confrontation
Sirius, Remus, James, and Peter were sitting together at the Gryffindor table at breakfast, quietly planning their next full moon adventure, when Marlene stormed up to them.
"You should be ashamed of yourself!" She glared directly at Sirius, hands on her hips. "Lily's been worried sick about Severus lately because you and Potter won't leave him alone, and then you pull this!"
James, Remus, and Peter all looked at in each other in confusion. Sirius alone had an amused smile on his face. "Poor Snivellus can't take a joke," he said casually. "It's not my fault he chose to sit in the snow and read. It's also not my fault that he made such a good target for my snowball throwing practice."
"What gives, mate?" James asked, looking mildly hurt. "When was this and why wasn't I invited?"
Sirius shrugged. "Yesterday. I was bored. You were showing off to some girl or other and these two were behaving for once - I'm ashamed, by the way," he said, eyeing Remus and Peter with mock disapproval.
"Shut up!" Marlene screeched, garnering the attention of everyone nearby. "You're so arrogant and conceited you can't even see how much you're hurting everyone around you! Why can't you just leave him alone?"
"Because he just makes it so easy," Sirius replied. "I can't even begin to be nice to such a greasy little git."
"It's almost Christmas! Haven't you heard of peace on earth and goodwill towards men?" Marlene was desperately trying to sway Sirius's opinion now.
"No." Sirius yawned and turned back to the sausages on his plate. "If we're done here, I'd like to finish my breakfast."
Marlene glared at him, seemingly considering how much trouble she might get in if she hexed him in the middle of the Great Hall, then turned on her heel and stomped out.
Sirius shook his head and took a bite of sausage. "Girls. Can't please them no matter what you do."