The Mrs and I have been dabbling in swinging for several years. We have had lots of fun, both fulfilling most of the fantasies. But there was still one big one to go.  The one we had spoken about for the longest and the one that got us the hottest between the sheets. A Bi MMF threesome. This is where we had built up to. We had both had Bi experience, Mrs was laid by my side as I sucked a cock, but we had never managed to...