An older man

The man who walked in was, in one word, underwhelming. He was short, balding with gray-white hair, and wore a white t-shirt underneath which his rather rotund stomach peaked out.

The two made eye contact but She quickly averted her eyes. Partly because she was supposed to and partly to hide her disapointment.

She heard a gruff voice murmur "Doggy style." and she quickly positioned herself. She got on her elbows and knees, arching her back as if to present her ass.

She heard the unzipping of a fly and felt him press himself into her. It couldn't really be described as fucking; it felt as if someone was repeatedly pressing their finger pad directly onto her entrance.

After a very short amount of time, filled with much grunting and gasping, the man finished, zipped his fly, patted her ass, and left.

The memory didn't trigger much emotion. It was something to think about, though. She had a lot of time to think.