Detective Comics 371 by Carmine Infantino & Murphy Anderson.
Batgirl rips her tights, but it turns out in the story she ripped them on purpose. Once the bad guys see her gorgeous legs, they are distracted and easily subdued by Batman and Robin. This would be considered sexist today, but as a huge Batgirl fan, I found it sexy that she knew she could use her beauty to easily manipulate and defeat men. Interior panel is by Gil Kane.
