You may be able to ‘bob’ back and forth between the two. But I kind of doubt it. The swapping couple I know personally - divorced after four years.

Sex is a hormonal ‘adventure’. It is most exciting with a new partner. For the best couples, it becomes more rewarding, but our bodies age and they physically adapt to each other - and the initial euphoria fades a bit over the decades.

We need to hang onto the excitement as best we can, just as we exercise so our bodies retain the ability to move easily and powerfully. But the old timers I grew up around settled for the trivet on the wall - “Kissin’ don’t last - Cookin’ do” (I think the ‘cooking’ part is a euphemism for responsible care and affection.).

Bringing in another person is one way that the bf exercises his “find a new bed partner” life skill, with permission. Do not ever believe that he will be satisfied with one new partner. Swinging and swapping is a lifestyle choice, not something like shopping at a new grocery store “Just One Time”, and you can walk away if you don’t like it.

I don’t know what your faith is, but mixing genders is a taboo for many modern religions. But how you were raised and how you anticipate raising your children, if any, should be something that you consider, because it will affect your self esteem. I expect that today’s children and tomorrow’s children will have immensely more information about their parents’ formative (and experimenting) years than in generations past. The diaries, the emails, the digital pictures will be turning up almost forever.

I would address several other questions, before agreeing: 1) How many second-hand sexual partners do you want exposure to? 2) Like Viagra, Exstasy, Cialis, etc., how does this make better babies and healthier children? 3) Are you ready to admit that your life, right now, is a perpetual date and not building a family? 4) Are you looking at a ‘3 coins’ permanent multi-adult family, or rotating bed partners (see #1 above)?

That said, the antics we see all about us pretty much argue that one-man-one-woman arrangements aren’t all that biologically cast in stone, that our bodies are quite capable of a lot of experimenting and mixing and matching. It is society and community that sets the rules we obey or disregard. Breaking taboos is pretty frequent for many lovers, for the added thrill of the fear (adventure, excitement, rebellion, assertiveness, whichever you call it for yourself). Be sure that you respect each rule, and understand how to be careful about each one you break.

Me? I suspect that most group sex urges boil down to interest in or curiosity about homosexual relationships.