She made an excuse and left , dragging Colin out behind her , closing the door with a wink that required her to use every muscle in her face . " Not very subtle , is she ? " Dom asked when the door was safely closed behind her . Lavender shook her head and laughed , though it didn't seem to ease his mind . 
Question: What may have caused Lavender to laugh at Dom ?
He made a snarky quip .