"Who's Bill the Face?" Harry asked, even though he was absolutely one hundred percent positive that was the least important part of Ron's speech. But that was basically a perfect analogy, or whatever, for how he'd been viewing what Ron had been doing, wasn't it? He tried not to concentrate on the stuff that didn't matter.
"No," he said a moment later, without giving Ron a chance to answer. "No. This isn't what we're doing, Ron - we don't need to be making more enemies, we have enough of those. And you definitely don't need to be drinking."
Ron had been the voice of reason more times on their little quest than Harry could count, when Harry wanted to trust his gut rather than listening to logic, and it was probably about time that he did the same for his friend. He sensed this leading to a fight, but it was too late (or too early) for him to care.
"I agreed not to sneak out to see anyone without telling either of you what I was doing, I think you should do the same. Because this-" he gestured, because he was losing a little bit of verbal steam, even though his resolve on the matter certainly hadn't weakened- "Needs to stop."