You study of course!

When the two of yoy have arrived at the library you head up to a quiet work are and sit down. Danielle leans down to grab her notes from her bag and you take the opportunity to look down her top at those gorgeous tits of hers. You can just see the top of her bra from this angle. It's black lace.
"Right." She sits back up and you quickly make it look like you were watching someone else in the library. "Which bits didn't you understand?"