Just watch

You watch for the next ten minutes as Adam brutally drills his dick into his sister's cunt, helping him hold her in place whenever she looked like she was about to get free.

"Oh god!" Adam exclaims as he thrusts deep inside her. "I'm about to cum!"

"Cum outside! Please Adam! I can't get pregnant with my brother's baby!"

Adam doesn't listen, further proving your theory that the virus has somehow changed the mentality of those who were immune to it. He hold still as he fires spurt after spurt of his incestuous semen into Sara's box. Realizing the futility of struggling, Sara just hugs her rutting brother and sobs as she's impregnated.

You clapped when he finally pulled out, dropping a broken Sara on the floor like a sack of meat, and to make sure that the semen stayed inside you shoved her panties into her no longer virgin cunt. Adam collapses on top of his sister, exhausted physically.

"That was quite a show. Hopefully in 9 months something will come out of it." You say as you pat Adam in the back as he rapidly looses consciousness. "I'll leave you siblings alone for now."

You head back towards your **** room and Lea glares at you, having heard the screams from the other room.

"What the fuck did you do, you monster?" She spits at you, hugging Gwen close to her chest.

"Nothing much. It was her brother that did everything really."

Her eyes widen in disgust when it clicks. It seems that her hate for you has reached even newer heights. "You're sick!"

"We're all sick in the head." You say as you start rubbing your dick back to life. "Now who wants to suck my cock? Watching those twins go at it made me really horny."