Address the elephant in the room

"Alright listen girls, before we start I'm gonna tell you Mia that Tracy knows about the text you sent about replacing her. I've noticed how competitive the two of you are around each other and I think I'd like to fuel that, so tonight we're going to have a friendly competition. I'll be testing both of you on a number of different things and whoever comes out on top gets to be my submissive little slut. Understand?"

The two girls look at each other with fierce expressions before turning to you and answering in sync, "yes sir." The game was afoot.

"Alright, follow me."

You lead the two of them into the living room where you've set up the toys you collected earlier. They crawl after you on their hands and knees. Once you arrive here you stand in the middle of an open area, the twins crawl up to you and kneel down in front of you, both staring at your crotch awaiting the cock they love so much.

"Alright first up we'll be testing your oral skills. The two of you are going to take turns sucking my dick and I'll decide which of you is better."

The two sisters look at you with a smile, clearly both confident that they have the better head game.

"Mia, since you're the visitor you can go first."

Mia smiles before using her hands to undo your pants and pull them down, revealing your cock which is already fully erect thanks to the appearance of the two sluts kneeling before you. Mia starts out well by spitting on your cock and rubbing it up and down with her hands. She then wraps her pretty lips around the tip, giving it a cute kiss before sinking it half way down her throat. As she pulls back up and lets your cock out of her mouth you can see the marks left from her lipstick on the tip of your cock. She then descends back down, letting out a loud gagging sound as she deepthroats your cock the whole way down, spitting up around the brim of her mouth. She then starts working her way up and down your cock with her mouth whilst simultaneously doing a twisting motion with her hand around the base of your cock. This whole time she hasn't broken eye contact with you once, except slightly when her eyes reactively started closing as a result of her deepthroating you. Mia continues on with these top tier cock sucking skills before you decide it's time to give Tracy a turn.

"Alright Mia, why don't you start playing with my balls while your sister has her turn."

Mia pulls herself off your cock and gasps for air before saying "yes daddy." She then moves down towards your balls which are filled with the cum you've been saving up all afternoon. She playfully licks them and occasionally pops one in and out of her mouth from her position between your legs.

Tracy then starts her turn. She seems to take a unique approach and rather than taking the lead, grabs your hand and places it on her hair, seemingly indicating for you to grab it.

"I want you to use my throat like the fuckhole that it is sir, please ram me down on your cock as hard as you like."

You smile at Tracy's ingenuity, clearly she's brought her A-game to this little competition. But nonetheless, you decide to test how dedicated she really is. First you grab her hair tight, before dragging her head over to your cock and ramming her down all the way right from the get-go. She lets out a gagging sound as you bury your cock deep in her throat. You then pull her back up so her lips are just barely wrapped around the tip before ramming her back down again so she's slamming her lips into your pelvis. You keep doing this hard and fast, filling the room with the loud *glurk* *glurk* *glurk* coming from Tracy's throat. After a while of this rough use of her throat, you pull her off your cock and she takes a deep breath as she finally gets a proper breath in.

"Thank you sir." Tracy manages to squeeze this in between breaths.

Her chin is covered in slobber along with some that has covered her tits. You position your hand beneath her mouth before giving her the simple command "spit."

She spits the saliva that's built up in her mouth onto your hand and you wipe it all over her face. She now looks like her true self, a sloppy, messy, depraved slut. Even Mia has slowed down her ball-sucking to stare at her impressive sister with wide eyes. You then ram her back down on your cock and continue skull fucking her as you had been before.

After another round of skull fucking your girlfriend you pull her off your cock again, positioning her directly above Mia. "Spit it on your sister slut. And then rub it all over her pretty face."

Tracy does as she's told and Mia gladly accepts her fate, looking up into her sister's eyes as she spits her saliva onto her face before using her hand to rub it all over. Both girls had put on some of their best make-up in preparation for tonight but you were doing your best to ruin that.

After using Tracy's throat a little more you felt you were finally ready to decide on a winner of the oral competition.