Emerson didn't let it show that he was surprised by her deduction. She was right. The more witches spent time with him, the harder it was to convince them that he couldn't be assed to spend time developing his talent. It was yet another reason he didn't stick around in covens for long and why he made such an effort to seem disinterested.
"I come across like a douchebag?" he chose to focus on that part of the comment, wincing. "You wound me." He never much liked talking about himself, and his tendencies to do what he did.