He came off condescending even in his straight off serious tone. He wasn't implying the girl couldn't do anything, the image in context had thrown him back a bit. She was bright and quick to learn if she'd picked up on the role he'd put her in mind for without him saying it.
"That," he said pointing to another name, Hersilia. "That's the current hole in my plight to find the right lead." Hersilia was the leader of the Sabine women and wife to Romulus, and so was what he used to base his script off of the Roman legend. However, Charybdis was much too little to fill that role, unless she blew him away with natural acting ability, which she very well could. It was up to her. "That," he said pointing to the name she announced, "As you've already picked up on is what I will give you."
"Because so many have already wasted my time," he said that seriousness back. "I'm a precisionist."