Having quickly discovered that the cute fellow who had come to chat her up was far more interested in herding her toward a dark corner than in a bit of harmless flirting and dancing, Cho had been looking for an excuse to get away from him without causing too big a scene. She was about at her wits' end as even the stinging hex hadn't seemed to have deterred him.
Then she spotted the perfect solution.
"Roger, darling!" she called, slipping away from the jerk and latching onto Roger's arm like a limpet. "What took you so long? I've been waiting for you." She smiled too brightly up at him, willing him to play along.