Sofie and I come out of our room, wondering where all our clean laundry is. Instead of doing our laundry, our pervy step-bother is caught lounging on the sofa, sniffing our filthy panties. We decide to startle and embarrass him about liking his sisters' panties. He tries to cover up his actions with some silly excuse, but we quickly shut him up, shoving the dirty panties back over his face, and then smooshing him under my ass. Sofie and I are conveniently in our bras and panties and we figured it appropriate to punish him while wearing our thongs to teach him a lesson. I go first, putting all my weight on his head while Sofie sits on his torso and laughs in amusement. She decides to take part as she grabs my ass, grinding it over his face and burying his nose deeper. Sofie quickly wants a turn so we switch places. I lean in close, enjoying every moment of watching him struggle for air. It turns me on to hear him gasp in between holds and I verbally him in the process. We keep teasing and humiliating him about loving our dirty thongs. We reapply the mound of panties over his face before Sofie reverse facesits him, burying him in the scents of our ass sweat. While Sofie covers him in the stench, I notice his dick is quite hard and growing in his pants. I pull it out and start stroking him against his will. Our helpless step-brother can't do anything to get us to stop. We decide to make him cum to our sweaty, filthy, panties while we sit on him, cutting off all oxygen. I keep stroking him as I switch places with Sofie, reverse facesitting him. I allow him some breaths as I humiliate him further and put him in his place. Then, Sofie and I sit back-to-back on his face at the same time, putting our full weight on his head, while jerking him off. He can't resist how good it feels and how much he will truly love filthy panties when we're done with him. We keep tormenting him with breathe play, asking him questions, and then cutting him off with another hold. All the while we're stroking him closer to orgasm. Sofie and I facesit him side by side, kissing each other passionately. We tell him if he wants us to get off, he has to get off! He has no choice but to blow his load all over my perfect ass, making a mess on me and all over himself! We tease him and humiliate him more for being able to cum for our nasty panties and sweaty asses, before leaving him in his own filth.