LatnLizard, my friend had a similar fantasy... her husband set up with a friend of the family that she knew and trusted & it would be agreed that the friend would "break in" their house, tie the husband up & force him to watch while the friend "raped" his wife...

the morning of the planned rape, the friend called saying he couldnt make it that night... well what my friend didn't know was that it WAS going to happen... it caught her off guard & she didnt put the pieces together until afterward that she hadnt really been raped... I guess she got really into it even though she THOUGHT she was being raped...

if you would like her full account on it, I'll go copy and paste it from her online journal...