A commotion in the stacks

As she does every night, Marian starts her end-of-day rounds with a trip up to the sixth floor, to make her way back down through the stacks, shooing any straggling browsers before her. The elevator is ancient and slow, but at least it's roomy enough on the trips when she isn't sharing it with a book cart.

It's not a surprise for the lights to be out when the doors open; this level is the smallest and doesn't hold anything that students need to check out very often anymore. What is surprising is the sound of voices coming from the far corner of the floor. She can't make out the words -- rows of books are rather effective at muffling that sort of thing -- but she strides purposefully toward the sound, rounding the corner just as the motion-sensitive lights warm up enough to illuminate the source: an array of hastily-discarded clothing around a rather muscular young man who has a red-haired girl pinned face-down on the carpet. Both are naked, and he's thrusting into her. Assuming she's stumbled across a in progress, Marian approaches with an angry "STOP THAT THIS INSTANT!", as she pulls out her phone to call the police.