The sister-in-law

My current girlfriend and her sister are Jehovah’s Witnesses, which makes this story even juicier because of the cheating.

This happened a few days ago. My girlfriend is doing some paperwork at her university to get her teaching degree, and well, I was left alone with her sister—she’s older than my girlfriend.

The thing is, ever since my sister-in-law found my girlfriend and me while my girlfriend was on her knees giving me a blowjob, tied up and blindfolded, she’s been “accidentally” catching us having sex or overhearing us fucking in the bathroom or in our bedroom, which is right next to hers.

Sometimes she’d find toys we usually use and I’d see her blush.

To make this short: I came back from work while my sister-in-law was making dinner. She doesn’t drink, so I had a couple of beers and we started talking. I brought up the times she’d caught my girlfriend and me having sex, and she blushed. Well, little by little she loosened up, and we ended up fucking in my bedroom—on the bed where I sleep with her sister. At first she seemed a bit reluctant because of her sister, but once we started, she didn’t stop moaning, and damn, she really does take after her sister in that regard.

When we finished, I made her give me a blowjob—something she never even did with her ex—which made me want to teach her many more things. Of course, we agreed not to tell anyone and keep it a secret from my girlfriend.

This morning, when I was dropping her off at work in my car, I asked her to give me her panties. She obeyed reluctantly (she really looks like her sister when she makes that pouty face). Well, I plan to fuck my sister-in-law again today, since my girlfriend is getting home late from work.