The Stranger

She looked up at her sir, with something akin to a mixture of fear and lust in her eyes. As was often the case when she saw him, she was on her knees, naked; her hands on her thighs, palms facing upwards.
“What are you?” he asked her sternly.
“Your whore” was her simple reply. Those were the correct words. She knew them, she felt them. Hell, she *believed* them. Which is why she was so shocked to find her cheek suddenly stinging from the swift and unexpected slap Sir just doled out to her.
“Louder. We have company, and he didn’t hear you.” He said, revealing a shocking surprise. She had no idea anyone else was here, much less another man. Was this stranger watching her right now? Dare she take a peak around the room to see if she could determine anything about this mystery guest? The simple fact that he told her they weren’t alone sent a shiver of electricity flowing down her spine, and to her extremities. And sent a fresh wave of wetness from her already glistening pussy. She bit her lip and tried to compose herself.
“I’M YOUR WHORE” she said in a much louder voice, but not screaming. She knew this night she had to be a submissive, and not even a bit bratty.
“Good Girl” he said, and she just about melted. Even after all this time, those words, from him, sent her spiraling into a magically wonderful place. “Would you like to meet our guest?”
“Yes, sir” she managed to mutter, in almost breathless anticipation. She heard soft footfalls behind her, then felt someone’s hand touch her shoulder. She looked up as a man, probably 8 or 10 years younger than she stepped around in front of her. He was completely naked, save for a mask he wore to hide his face. She wondered why the mask, but didn’t ask. She knew well enough that her role in this was as plaything. And she so relished that role.
“Do you like our guest?” He asked her, and she curtly nodded. “Show him how much you like him. Suck his cock. Show him how much of a whore you are for me.” Her eyes flashed a devious smile his way, conveying how much she loved when he did this to her, but also how much she trusted him. She leaned forward, careful to not move her hands from her thighs, and took the stranger’s stiffening member into her mouth. Within seconds she was gagging on this newcomer’s cock. She knew both men were watching her do this, but she was only performing for one. She needed HIM to enjoy this, not this man she had never met before.
“Does my precious little slut have skill?” she heard him ask the man who had his cock in her mouth. She looked up, and saw him nod, but not speak. He noticed this, and said “He isn’t allowed to speak. That is the deal. He can play, and have fun, but not speak. I don’t want you to ever know who this man is.”
*That explains the mask* she thought, while getting even more turned on by the idea of the whole thing. *I could KNOW him!* fear told her, briefly, but she flushed it away, realizing he would never do that to her.
“I think our guest would like to fuck you now.” He told her, presenting her with a condom, still in the wrapper. She took it from his hand and began to tear it open, when she felt him lean into her ear and whisper “the rules still apply. You may not cum unless I AM inside you.” Her breath caught, her pulse raced. That was almost an impossible task, and completely unfair. But she was too far gone to turn back now, and she removed the condom from the wrapper, and rolled it down the mysterious gentleman’s cock.
He pointed to the bed, and she laid down spreading her legs wide, as she had been taught. The stranger positioned himself and slid inside her in one smooth stroke. As she began to get fucked, she had to dig her nails into her hands, and bite the inside of her cheek to prevent herself from cumming. She lasted for several long minutes of torturous agony, before blurting out “PLEASE, SIR! MAY I CUM?!?!”
What surprised her most was not that he said no, but that the stranger stopped.
She looked around the room, and saw him undressing, and the stranger slowly stroking his cock keeping it rigid and full. She watched as her sir walked, naked, to the other side of the bed, and laid on his back. His cock was already hard.
“If you want to cum, you know what to do.” he told her. In a flash, she was on top of him.
Lowering herself onto his bare, hard cock, she felt the pent up orgasms begin to wash over her, and she shuddered and half screamed in the intensity of the pleasure. She leaned over him, as she rode him; locking eyes with him. She noticed an almost evil twinkle in his eye, when she felt his hands on her hips, slowing her gyrations. Her skin tingled as his hands when around to the cheeks of her ass, and began to spread them open. Her breath caught when she felt the almost forgotten stranger’s freshly lubed finger probe her anus. She suddenly realized what was about to happen, and she let out a shuddering breath of lust and anticipation.
He had never let anyone else have her ass, while they had been together, but he told her that when she received her first double penetration, it would be done this way. So he could watch her eyes. And he did. She locked her gaze on his, and forced herself to relax as she felt the stranger get into position and push his cock into her ass. She couldn’t believe how stuffed she was. She lost all sense of herself, and just floated away into subspace. All she could do was FEEL. And it felt marvelous.
They fucked her like that for a while, before the stranger began to grunt, and she felt the tensing cock that signified he was filling his condom with cum. The three of them slowed to a stop, allowing the stranger to withdraw.
“Thank him, and tell him goodbye” Her sir commanded. She did so, and watched as the masked man left the room, and disappeared.
The rest of the evening was a blur to her. She wouldn’t have been able to remember the details if she had to, but she knew she loved every minute of it just as much as she loved everything about this man, her sir.

Source: reddit.com/r/Erotica/comments/beijht/the_stranger