She slammed the door behind her.
Nice girl. With her gone, though, the air felt a few pounds lighter.
Many people had said that the though is unnecessary. However, this is how I read it: The girl slammed the door (a rough action). She was a nice girl (sarcasm), but I had to admit that the tension dissipated once she was gone.
So the though corresponds to the but. Or maybe I'm mistaken?