It's perfectly fine as you both seem to be ok with it. My wife and I have a shared male lover and she encourages me to invite him over pretty often, most times to watch he and I sucking each other off. She loves to watch us together and most times joins in the fun but there are times where she lets us have our fun alone. Just this past weekend Tom was over for about four hours of suck time. We get together and can't stop sucking each others cocks. After Tom left my wife says "You guys are something else to watch". She did stop in on us to eat a load of his cum, he cums a lot and did so like 7 times that day.
I would think the knowledge of knowing your spouse approves and encourages removes all remaining inhibitions . Makes me hard to think of it, I'd love to suck cock for my significant other.
You're exactly right, for many years of my first long term marriage I was on the "down-low" with my desires so being married to a woman that supports and enjoys my bisexuality is liberating. I no longer have to hide my sexuality from my wife and most importantly we share in my sexuality which bonds us even closer together.
mine used to.......used to look at waiters n random guys and discuss if they were attractive to us simon