Harry grunted at the impact of the elbow, eyes narrowing behind his glasses and foot kicking "accidentally" into Ron's ankle as he moved away. He shrugged shortly at Hermione. "At least I know I know how to swim. It's not as if we can do any of the other shite you have us trying." Nevermind that he'd been the one pointing out that at least they were trying, a few moments before. When Ron was complaining.
Harry seriously wanted to punch Ron. And really, it wasn't as if he'd never wanted to punch Ron. But he knew that this wasn't them. He gritted his teeth. "Look, I know that it's my night with the thing, but it's in the dorm with Ron and me twice as much. I think it's got the others in there about to blow too. You take it tonight and give them a night away. I'll take it tomorrow instead," he told Hermione, breathing in through his nose and forcing his tense jaw to relax. Before he teeth started grinding.