Rachel didn't know that Leslie had been waiting for her message all along.
He knew that he might not be as smart, or rather, as "cunning" as Connor, but he still hoped that Rachel had once taken their relationship seriously. He hoped that Rachel would say to him, "I miss you." If she did, no matter what she had done before, he would forgive her.
However, Rachel had actually questioned him about Trevor. Had she already seen him as someone who had fallen from grace? This made Leslie even angrier, and he couldn't control his tone.
Rachel of course detected the sarcasm in his voice, and she hadn't expected that Leslie had already started seeing her as a careless woman. Not only had she contacted Connor after breaking up with him, but now she was still entangled with Trevor... It was simply
