Riku was too busy finding Kairi's journal entry (http://once-royal.livejournal.com/1516.html) and the conversation with Namine about her capture to see Sora's reaction to his news.

"Here," he said when he found it, holding his journal out so that they could both look at it together. "This jerk named Axel and the people in black robes, they--" He broke off when he looked over and saw the look on Sora's face.

"What's wrong?" Riku asked. It wasn't like his best friend to suddenly go emo. Damn, he'd even smiled right before stabbing himself with the Heartbreaker.