Tl;dr – fucked my girlfriend’s sister on her 18th birthday

Girlfriend – Riley

Sister – Claire

In all honesty I always felt some sexual tension between her sister and I, but obviously that’s wrong – who fucks their girlfriend’s sister?

When we’d shop with her family, she’d always ask me to go to another store with her, zip up her dress, see her in the outfit. She always made a point to have my attention. She’s one of those hyper-fem bi types and she knows it turns me on. The fishnets, the skirts, the tight shirts and high tops.

But I always knew it would never happen.

One night we were celebrating Claire’s 18th birthday. We played games, drank a bit, watched a movie as a group. As her friends started to leave, Riley and I were getting frisky under a blanket, teasing each other. Before long we couldn’t take it and she grabbed my arm and announced to the room we were getting some sleep.

As soon as her door latches we’re making out and both get naked. Petite and pretty thin all around, Riley was the less endowed of the two physically. After some time exploring each other’s bodies, we decided to try blindfolds again. She tied me up and covered my eyes.

She said “I’m gonna grab a toy, I’ll be right back”. The door closed. A minute later it opened.

“God, you’re killing me. I can’t wait to fuck you so hard.” I say, to no response.

I feel her get on the bed and straddle me. She teases her vulva with the tip of my dick and she’s dripping with desire. She begins to slide it in more and more.

“What about the condom?” I say.

She leans down and I feel her breasts on me. “I wanna feel you, all of you.”

It was Claire.

And before I knew it she grabbed my dick and I was deep inside her recently virgin pussy. It was perfectly tight, gripping me.

“Claire! What the f…”

“Sh… Don’t worry, no one will know.”

She starts thrusting and grinding on me… I’m as hard as I’ve ever been. She removes my blindfold and see her… Short but so full. Petite, yet developed breasts… An innie pussy. Her ass and hips wide and curvy. She put her hand on my mouth and started bouncing up and down on my cock. I swear I grew another half inch in her as I felt her pussy lips grip me.

“Jesus… I could explode like this… ” She said. She reached over to get Alice’s vibrator and put it right on her clit. In minutes I feel like I’m about to blow.

“Claire… I don’t have a condom on…”

Between moans, “I know… That’s how I want it.”

“Claire… I’m so close… I…”. Her hand went over my mouth again as she started to quiver and pulsate.

“Fuck, I’m gonna cum…”

And so was I. She exploded on my cock and she moaned in my ear my name as she throbbed on me… She kept riding me till I couldn’t hold it anymore.

“Clmmm… I’m… Um” Her hand over my mouth as I tried to warn her. Her hand left my mouth and she kissed me deeply as I filled her up with a week worth of cum. I melted beneath her as she kept going till I came again. My cum so deep in her.

She reached behind her and grabbed a 5″ dildo. She slid me out and immediately replaced it with the dildo… Not a drop came out. She put her underwear and skirt back on, blindfolded me again and left without a word.

A minute later I hear the door open again. Riley came in apologizing.

“Fuck I’m sorry, had a friend call for an emergency. Now where were we?”

And I couldn’t get hard at all… Claire had left me a mess and all I could think about was her.

That night I got a snap from Claire… It was a video of her creampie with the caption “no bc to stop your swimmers… Miss you already”

And this was just the start of my affair with her sister. Would love to post more.