Hermione's brow furrowed. "No, I haven't. He's probably out by the lake." But Ron asking after Malfoy is like Harry suddenly deciding to like said lake and the Malnosso. "Why do you ask?"

Still clueless about the real reason, she's figuring he and Malfoy had another disagreement of sorts and now Ron's wanting to find a way to blast a hole into his skull. For multiple reasons, she did not want this to happen, not limited to the fact that her other best friend would have a fit.