Hi there,
I reckon that this is cuckolding, but simply in a circumstance when an alpha male has already found an alpha female and they want to have a submissive male augment their relationship. Make no mistake, alpha’s are instinctively drawn to lead, to dominate others, albeit sometimes in a very considerate and constructive way (think of a great boss at work). I can certainly picture a scene where such a couple might want to recruit a submissive male. But he would have to be very trustworthy. Just don’t get lost in sexual slavery to such a couple-beware humiliation and control gone to the extreme. Two very powerful people could develop very powerful fantasies.