Cocksharing

Once I slept with my best friend`s ex husband ( don`t panick she does not mind ).

We were flatsharing at that time, and the flat was robbed. He was one to discover - dropped in to feed our cat, since I was staying at my friends place feeding her cat (never noticed how these cats nursing, flower watering shifts may turn out to be sexy?) and my best friend (his ex wife) was out of the city taking her exams. 

So in addition to the robbery secret (to save her nerves) we shared another one that night. 

He turned out to be a lousy fuck - I told her about but nerve dared to share my observation...

Any experiences alike?