Calmly

"I see that you two are having fun again. Just you remyember what I said young man and don't get your sister pregnant" she said apparently not at all shocked by the sight of her naked children pleasuring each other.

"Don't worry" Becky said as she jumped to her feet, causing her perfect tits and ass to bounce "I'm on the pill. Besides he came on my face, not in my pussy"

Sam was still sitting on the sofa as Becky began to wipe her brother's cum off her face with her fingers. She sat down in his lap, pressing her ass against his spent cock, before licking her fingers clean.

"Yes I can see that" her mother said "but I've listened to your…intimate moments before. I've heard you begging for Sam to finish inside you"

"Just stop worrying" Sam said "we're always careful"

"Oh are you now?" His mother asked "is that why Jenny told me that she saw you having sex with my neighbor's daughter while she was out running. She told me you were fucking her at the open widow, looking over the street"

"Well she's quite the exhibitionist" he said.

This is insane. She knows her two children are fucking each other and she's fine with it. Still, the more wrong this got, the more it was turning me on.

"Yes well maybe you should try and be a bit more subtle in the future. Just because some slut wants to fuck where the whole neighbourhood can see…"

At this point I sat straight up so she could see me for the first time.

"…you guys didn't tell me you had a friend or that she naked. Hello Ashley, I don't think we've every really spoke before, I'm Carrie. I've heard you've and my son have been getting to know each other a little better. I just hope that you two will be less public with you're affection for each other"

"Well you might what to ask Sam exactly who's idea it was in the first place" I said

"Sam? Something you're not telling me?" She asked

"I…blackmailed Ashley into having sex with me" he said reluctantly.

"Really? So why is she over here naked?" She asked. I noticed how Carrie's eyes lingered on my naked body. I began to wonder if she was getting a few ideas.

"I have naked photos of her. Unless she does exactly what I say I'll send them to everyone at school" Sam said