"Maybe you could toss on a pair of shorts. It's distracting like that."

Distracting? Not exactly the right thing to say, but he ran with it.

"If customers come in, they won't be looking at the books."

...Not smooth, but truthful. And he was ever so fond of being blunt and straightforward. It just made life easier. She looked good, and she looked better in that. Why not tell her?