As told to Laura Jackel.
It began innocently enough. Karen*, a busy married mum-of-three, noticed dad Simon* when dropping her eldest two children at school.
"We would exchange smiles and platitudes about the kids. I learnt he was working part time as a builder and was at home a lot with his girls," Karen tells Mamamia.
"It began to get a little flirty last Christmas with the occasional cheeky text message. We didn’t see each other over the summer break so when we met up again at school in January, the sexual tension was high.
"That night he sent me an explicit text message describing what he wanted to do to me, and I almost dropped my phone."
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Karen and Simon began seeing each other for sex once a week. In between each clandestine meeting, there were dozens of lust-filled online exchanges.
"It has been very fast and very intense. The sex is kinky – we dress up, tie each other up, and act out fantasy role play scenarios. I can tell him exactly what I want and how I want it.