any time a third person entered any 2person relationship i was in, the relationship suffered, so i rejected exclusivity.
i have discovered that indulging in fantasies resulted in nothing but physical pleasure.
the emotional/spiritual/medical results were not good.
after a decade of dead end promiscuity and perversion, exploring and experimenting, i became celibate, abstinent, and eventually monogamous and married.
in april is my 23rd anniversary.
my wife and i are still in love.
from my own personal experience, i do not advocate indulging and engaging in sexual fantasies which involve more than two people.
but that is only because i have already indulged and engaged.
i would not know what i know, had i not done what i did.
i did not listen to others who urged restraint.
i learned the hard way.
hope this helps you.