One of the closest times I've come to being caught: This was my second meet with a guy I found on a UK swing site. I noticed his flat was unusually bare and did not look "lived in" but he told me he was single and lived alone, travelling most of the time with work - not that I bought any of it.
Turned out he was married, with ******* and the flat he was using for entertaining his lady friends belonged to his wife, they were renting it out and it was empty in between tenants.
I had been with him for just under two hours when she turned up, finding him using an App or something on his phone from what I overheard and had tracked him back to their flat. Luckily, they only had one set of keys (which he had) so she couldn't let herself in so she resorted to constantly buzzing the intercom and phoning his mobile demanding to come up. He was panic stricken, I've never seen anyone so frantic in my life - I wasn't happy about it either to be honest. Eventually he calmed her down over the phone telling her nothing was going on and he'd be down in 5 minutes - I threw my clothes on and we both left flat together, I took the lift to the top floor so I could sort myself out and then leave five or so minutes later and he went down to talk to his wife. Little did he realise the amount of explaining he'd have to do when his wife walked into the flat only to find a empty bottle of wine with two glasses, a messed up bed and a bedside table littered with torn condom wrappers/boxes.
I could hear their argument as I walked over to my car as all the windows in the 3rd floor flat just above the car park were open - she wasn't very happy with him. He did phone me up the following day to come clean and apologise but I never heard from the guy again after that and his profile and long list of meet verifications vanished......