Sharing With Our Neighbours

We both kind of knew we'd eventually get caught, as we were having gay sex in each others houses. Or that someone else (nosey neighbours) would let the cat out of the bag.
What we didn't expect, was our wives to not only be ok with us fucking, but also to want to be involved.
It was my wife who caught us. Jim was fucking me missionary on our sofa when my wife walked in.
Her dentist appointment had been cancelled, so as Jim was cumming up my arsehole my wife watched him empty his balls deep inside of me.
When we realised she was there, I fully expected all hell to break loose. But instead I saw the lust on her face and heard her say "Wendy and I knew you two were fucking". Wendy being Jim's wife.
The discovery has transformed our respective marriages.
Jim and I now have sex pretty much every other day. And so do our wives.
Because we live only a few doors down from Wendy and Jim, we often stay over at each others houses. The girls from what I now know, decided after finding out nearly a year ago, to go down the route of 'What's good for the goose, is good for the gander". And so they've been having sex together without us even suspecting.
We have had a foursome recently, but my wife didn't like me fucking Wendy. So afterwards she Told me just to carry on fucking Jim and let her and Wendy enjoy themselves.
Pity because Wendy has such a beautifully large clit I enjoyed sucking on. A clit no doubt my wife thoroughly enjoys.