Mia

After about 15 minutes of having the vibrator sandwiched between their pussies at the highest setting, it's Mia who can't hold on any longer. Her moaning gets louder and louder until her pleasure finally takes over and her pussy starts gushing straight up into her sister's before dripping back down onto the table.

"Oh fuuuuuck! I'm cumming! I'm cumming!" Mia pulls off of Tracy's lips and squeals out as she can't hold off her sweet release anymore.

As she comes down from her orgasmic bliss she looks to you. "I'm so sorry daddy. I couldn't take it anymore. The pleasure was just too much. Please don't be mad at me."

"Don't worry whore, I'm not mad at you for cumming, that was the purpose of the trial, all you did was lose. But I am disappointed that you forgot to announce you were cumming properly."

"Oh fuck, I'm so sorry daddy. I won't let it happen again."

"No, you won't."

Tracy continues softly moaning to herself throughout this conversation, looking too overwhelmed by pleasure to even take in what you and Mia are talking about. You're impressed she's still going this long, clearly all that training with a vibrator in her pussy at work is paying off. With the trial over you move around to untie the restraints holding the sisters in position, but Tracy still doesn't move, clearly too high on lust to even be aware of what's happening around her. You push her, rolling her off of Mia and the vibrator, which finally wakes her from her pleasure filled trance.

She looks at you and asks "did I win sir?"

You chuckle before answering. "Yes you won slut. Did you not feel your sister squirting all over your pussy?"

"No sir, I was too out of it I guess."

You're impressed by this and decide Tracy deserves a reward. You pick her up by the waist and place her on top of her sister, but now they're the other way round so they're each facing the others' pussy. Tracy instinctively starts licking her sister's pussy, cleaning up the remnants of her squirt juice still left on the outside of Mia's pussy. As she does this you slide your cock into her pussy and start fucking her hard, bringing about a new wave of pleasure and making her moan into her sister's cunt. Mia helps add to this pleasure and starts licking Tracy's clit from below. It's not long before Tracy's on the verge of orgasm once again.

"Oh fuck sir, please keep pounding my pussy hard. Just like that! Please sir, can I cum! Pleaaaaase!"

"Alright slut, cum for me." You pump into her pussy a few more times before pulling out and using your hand to aggressively rub the outside of her pussy.

This almost immediately causes her to start gushing straight onto your hand and down onto her sister's face.

"Oh fuck! I live to serve! I live to serve! I live to serve!"

Tracy can't help but stop licking Mia's pussy and instead starts squealing out as she climaxes. She starts panting for a moment, before pulling herself together and diving straight back into her sister's pussy. Mia feels this and follows suit, returning to lapping at her sister's clit.

"Alright, now it's my turn to cum." You say as you sink your cock back into Tracy's pussy.

You start fucking her just as hard as you were before, which causes your balls to slap into Mia's forehead repeatedly. She takes this as a sign and starts periodically switching between licking her sister's clit and catching one of your balls in her mouth, sucking it to add to your pleasure. It's not long before you're ready to cum once again. As soon as you start feeling your climax coming on, you slam your cock balls-deep into Tracy's pussy and unleash your load deep in her hole.

"Oh fuck, I can feel your cum filling me up sir. It feels so warm as you fill up my insides."

After you cum down from your orgasmic high you pull your cock out of Tracy's pussy.

"Why don't you suck my cum out of your sister's pussy, whore. But don't swallow it, she earned that treat for herself."

Mia looks slightly disappointed that she won't be able to enjoy your salty jizz, but she does as you instruct and starts desperately trying to suck your cum out of Tracy's pussy. Tracy helps out and does her best to contract her pelvic muscles to push the cum out of her cunt. After a moment Mia's eyes widen as her mouth is filled with the salty treat. She takes her time to make sure she really gets the whole load out before pulling her face off Tracy's pussy and opening her mouth up to you to reveal the massive load that you had deposited in your girlfriend's fuckhole.

You give Tracy a playful smack on the ass before saying "come get your reward slut."

Tracy giggles as she flips around so she's face to face with her sister. Mia then unexpectedly flips Tracy over so she's on top, before slowly dripping the cum into Tracy's hungry mouth. She's panting like a cum addict as she awaits her treat. Mia lets about half of the cum in her mouth trickle out into Tracy's before moving in close and taking a more direct approach to giving her the rest, passionately making out with her in order to transfer the rest of the cum. Once she feels she's given Tracy all of the sticky white fluid, she pulls their mouths apart. A thick strand of either spit or cum connects their two tongues together, but Mia spits straight into Tracy's mouth in order to make sure she gets all of it.