I'm To Blame

About sixteen weeks before my mother I law passed away, my wife asked me if I'd do something extremely special for her mum and for her.
When I asked what, my wife asked me if I'd have sex with her mum.

I'm reasonably well endowed and my mother in law had apparently found out from my wife. They'd schemed together and came up with the idea of giving M some good times before she passed.

I could hardly say no, and besides even though M was dying, she still looked good.
The first time we had sex, M and I, I was extremely cautious and tried to be gentle, but M was having non of it, Telling me to fuck her hard.
It was an amazing afternoon where I had some of the dirtiest sex I've ever experienced. In fact M was a far better sex partner than her daughter.

Afterwards back at home, her daughter didn't ask me about any details, but just wanted to know if her mum had enjoyed herself.
Without telling her anything about the sex itself, I let her know her mother had experienced everything she wanted to.

Two days later I was back round at M's, and if our first time was horny, then our second time fucking was unbelievably filthy sex.
There wasn't much we didn't do together. In fact the only thing we didn't do, was pain.
Everything else was open with us both and I could tell it was one of M's wishes to experience things she'd never tried sexually. Things I'd not even done with her daughter.
If you've a broad enough sexual imagination and then some, you'll probably understand what we got upto.

After several visits, I turned up ready to indulge M in some serious anal fucking and fisting. Only to walk in on her having sex with one of my wifes female friends.
I was about to turn around and leave when M told me firmly "Get in here and fuck us both".
It was one thing to have sex with my mother in law, because my wife wanted me to. But I wasn't sure about fucking Becky, even if I'd always fancied her.

It was a pure whirlwind of sex, where at the end I'd cum three times, twice inside M, and once deep up Becky's arsehole as M tongued her pussy and clit.

Giving Becky a lift home afterwards, she told me my wife didn't know about her and M, so I've never said anything.
But there is another reason too.

That wasn't the only time all three of us had sex together. We actually had sex on several occasions before M started to become too ill. And it was around that time that I had sex with Becky on our own.

She'd witnessed many things that M and I had done together and wanted to experience them herself. So with her boyfriend out, I took Becky back to her place and fucked her like a common slut.
Her boyfriend, her words "Just doesn't fuck me this way".
And to be honest, before M, I'd never fucked a woman with the downright nastiness of anything goes sex.

Sadly eight months ago M passed away. During the funeral my wife actually mentioned that her mother had had a good time prior to becoming too ill. Myself and Becky who was at the funeral, understand my wifes meaning and shared a knowing look.
We'd also shared the look, because the day before myself and Becky had enjoyed sex outdoors together.

Without my wife asking me to have sex with her mum, I know I wouldn't have cheated on her with Becky.
But the more Becky and I have sex, the more I want her and her need to experience dirtier and ever harder sex.

I'd love my wife to share herself with Becky and I, but I know that will never happen. So for now at least, Becky and I will meet up apart from out partners.