Grandmother is a Filthy Tart

"I ... I might get pregnant," Tabitha moaned. "And he's my brother. I can't do it with him."

"Of course you can," our grandmother said.

She eased forward off my cock, the gape of her cunt a quick scarlet wink as my grandmother moved aside, her fingers working Tabitha's clit.

"I'll just lick this," my grandmother added as she threw a glance at me. "Then I want you to fuck her, Mikey."

My sister gasped when her grandmother ducked in while she also settled onto her front, her face between Tabitha's thighs.

"God ... Oh fuck ... Gran, please..."

"Put your cock in her mouth," my grandmother gasped to me. "Shut her up. Make her suck it, Mikey. She can clean my twat off that thing."

My sister stared at me for a few seconds when I complied. She writhed and moaned, eyelids fluttering while her grandmother sucked at the bean.

"Tab," I grunted as I wanked my size.

"I don't believe this," my sister mewled, eyes full of shock.

"Suck it," I growled as I shuffled in close on my knees.

"Uh, Mikey, you're my brother..."

"And she's my grandmother but you just saw what we were doing."

My sister hesitated for a few more seconds, then gave it up with a groan.

A moment later I was staring down to where my own sister's lips pursed around my cock, the wet liquid swirl of her tongue teasing the banjo string as she held me with one hand, a smirk firing across her face while her eyes showed devilment, her features suddenly showing a much younger version of the woman who was slurping at Tabitha's labia.

My sister sucked at my cock, licking the bulb while she stared at my face. I saw her wince, presumably from pleasure as her grandmother licked and lapped, a groan bubbling forth from Tabitha, her hand working my size.

As she gazed at me, Tabitha murmured: "How did this happen?"

"It's her," I said. "She just takes over."

On cue, my grandmother came away from my sister's pussy. "Put your cock inside her," my grandmother gasped as she rose up onto her knees.

She was naked, big tits swinging util she mauled her own breasts.

"Kiss me," my grandmother ordered. "Taste her sweet pussy."

My grandmother slid her tongue into my mouth, her hand on my cock while she gasped into my open mouth. As we did it, my hands went to her boobs, their weight in my palms before I mauled their size, the need to rut urgent in the pit of my stomach.

When the kiss broke and I saw my sister with her legs spread, the tiny, precise triangle of her pubic thatch at the apex of her neat-lipped slit, I growled and got to where I could give her the cock.

"Oh, Mikey, what are we-?"

My sister's eyes went huge, the cockhead breaking beyond the slick and tiny resistance of her entrance stopping her words.

"Oh, yes, my darlings," I heard our grandmother gasp.

Then I was inside my own sister, my hips starting to work while Tabitha gasped and reached up to curl her fingers over my shoulders.

"God, Mikey, I don't fucking believe that's you. Uh, what am I doing?"

Even as she said it, Tabitha's pelvis was moving, her cunt taking all I had as she thrust up to meet my downward stroke.

For the next twenty minutes or so, it was carnage in my grandmother's bed.