"So, are you ready to do this?"
"Yeah, Sprig… be mine, big brother…"
Polly climbed onto Sprig, lining up her cunt with Sprig's member, and took the plunge. Both of them moaned at the contact.
"Sprig…"
"Polly…"
Just the feeling of Sprig's cock deep inside Polly's cunt was enough to cause immense pleasure for both of them. The two caught their breaths before Polly began moving, slowly at first, before speeding up a bit.
Sprig's hands found Polly's mounds, and he began feeling them all over, giving Polly more pleasure.
"Oh, Sprig, you feel so good!"
Sprig moaned loudly in response, unable to say much else as he was drowning in pleasure.
So was Polly. She was bouncing on Sprig's cock very fast by that point, and she quickly came once more.
"Oh GOD! Sprig!"
Sprig then took one of Polly's tits into her mouth, and started sucking on it. Polly screamed loudly at the added pleasure.
"SPRIG! AAAHHHH!"
Sprig moaned into Polly's breast in reply.
It was only a matter of time before they felt another orgasm approaching, and with how wild Polly was riding Sprig, their peaks were fast approaching.
"Polly! I'm gonna cum again! God you feel so good!"
"Sprig, do it! Cum for your little sister, knock me up!"
"Polly! Aaahhhhhh!"
Wave after wave of hot seed fired into Polly's waiting womb, quickly filling her to the brim. The feeling of being filled so much was enough to send Polly crashing into her own orgasm, her and Sprig's combined fluids covering their crotches and the couch beneath them.
"Ummmhhh… Sprig… That was amazing! Thanks for the good time…" Polly panted, finally relieved from her painful heat.
"Glad… I could help…" Sprig panted in response.
Exhaustion soon overtook them both, and their eyes soon drooped.
"Night, bro…" Polly soon fell asleep, Sprig still buried inside her.
"Night, sis…" Sprig followed Polly into dreamland, his head resting on his sister's chest.
The Plantar family legacy would live on...