Attack her mind

"Yes. Sarah. Yes" You whisper right into her ear "It is the new world, lass. " You say the next world louder so her brother can hear "We. Men. Will use you every time we want, right Adam?

"Yes! Yes! Yes!" You are not sure if Adam agrees with you or just accompanies his thrusts with moans of pleasure.

"So..." You continue looking straight in Sara's frightened eyes "You are our ****. We will use every hole every time we wish. And your brother doesn't care that you came to this world from the same cunt as he did" You let yourself to weaken the hold on Sara's waist and instead fondle her tits. "The virus changed men. " She lets out a painful moan when your rough squeeze combines with yet another squeeze.

"Oh god. I am about to come" Her brother says a loud causing a new wave of panic in a helpless girl. She tries to say something, but you close her mouth with your palm "I suggest you to switch holes. Take the opportunity before I claim her anal virginity for yourself"

He looks at you with disbelief but just in few moments hi smiles and pull away from Sara's ravaged cunt. You take your palm away from the teenager's sweet lips to hear "NO! No brother!!! NOOOOOOOOOOO!!!!!!"

He pushed his dick right in her ass without any sing of mercy and after few violent pushes he finishes inside her, falling exhausted next to her trembling body

"So. Adam. How do you feel after **** your little sister?" You ask releasing Sara from your grip. She is too shocked to go anywhere anytime soon