The father

As you walk down the hallway, you can hear voices at the other end where the light of a exam room is on. At first, you think it's just normal conversation, but as you get closer, you realize what the sounds are. It's the unmistakable sounds of people in heat, groaning and grunting in pleasure. You stop outside the door and wait, listening to the sounds of heavy breathing and the occasional "yeah... yeah..."

Gulping, you grip the door handle and try it. It's not locked and it turns. At this time of the day, there must be no other doctors left, although you wonder if the receptionist knows what's going on here. She might, which must put her in an awkward situation of looking after the little girl outside while her father is occupied.

You crack open the door just enough to slip in, and you're instantly greeted by the sight of the back of a man in a suit with his pants and boxers around his ankles, facing the examination table in front of him. In between him and the table, is a woman with long brown hair and a doctor's white coat flipped up over her back, and she's resting on her elbows as the man drills her from behind. You can't see her face, but from the familiar moans and view from where you are, you know it's Robin.

You hold your breath and take a few steps closer and to the side to get a better look. Robin's skirt under the coat is hiked up to her waist, while the white panties she has on is pushed to the side to allow the man access. As he thrusts in and out of Robin's pussy, you see that he's wearing a condom.

"Are you close?" the man asks. He's middle-aged with a little grey in his hair.

"Not yet... keep going..." Robin's voice all but confirms her identity. You feel betrayed, although you're not sure if that's the right reaction since you already knew Robin is married and you had met her at a rampant sex party where you know she was with other men. You stare blankly for some time, thinking about what to do or what the appropriate reaction is, not quite paying attention to the two people having sex a few feet away from you until Robin gasps and shrieks before she bites her lips together to stop herself from getting too loud. You regain your focus and see Robin shudder against the examination table as she reaches climax and the man behind her groans in relief. You can see the sweat on his brow from the exertion of having to please the younger nubile doctor. He lasts about 1 and a half more thrusts before he backs out of Robin and slips off the condom, allowing his cum to spray onto her ass and the floor.

After that, both of them are breathing heavily as they recover. Robin doesn't look back as she leans forward, while the man eventually pulls up his pants and gets himself presentable. "I'll see you again for Ella's next appointment in 2 weeks?" he says.

"Sounds good," Robin replies, still not ready to get off the table. The man stares at her ass for a while before he turns to leave, shutting the door behind him. Still invisible, you gaze at Robin, who's oblivious to your presence.