"Because if I stay, we're going to have another fight over bloody, fucking Peter," Sirius said, exasperated, his hands tossed up in the air as he spoke.
He also knew that it was the week of the full, and he knew that Remus probably felt like shit. And if they ended up having a fight, it would definitely be his fault because of that.
But now, with the words out in the open, and even though Sirius wasn't even facing Remus, he was fairly certain that they were going to have a fight anyway. He turned on his heel to look at Remus, promising himself he would leave right after this.
"But I'm fucking glad Harry hit him," Sirius said. "And I hope it fucking hurt."