Never had the luck to be involved in such a fun conversation. However, my wife has had some interesting conversations with her sister. She never tells me about what, except 1 time. That was shortly after the 1st time we all saw eachother naked at the sauna. Apparently my SIL thinks I have a rather big and nice looking dick 😁. Always fun tot hear such a thing, specially coming from SIL!

Book club
 

Years ago, my gf (now wife) and three of her friends were reading the "Shades of Grey" series as they came out and would have get togethers at our house and discuss each chapter as they finished it. I interjected here and there as I caught snippets of the conversation, but it got really interesting when they finished the first book and went on to the second.
By then, I was interested enough to pick up my wife's copy of volumn one of the series and start reading it. The women were genuinely interested in a man's view of the books and I became part of the group through the end of the series.

Many interesting conversations were had about the characters and incidents that were had in the books and included how I would have handled certain situations portrayed there. Many times the conversations got personal between the five of us, including cock size (both real and preferances), our bedroom antics and our fantasies, what kind of private grooming we liked. That's where I first heard of "manscaping", (believe it or not!) and that my future wife liked it. By the time the group broke up, everyone knew that I had gone from natural to nothing, lol. My gf had shared photos of me with the other ladies in the group, but I didn't know it at the time. Unfortunately, nothing more ever happened between the five of us, but I know the ladies enjoyed our talks as much as I did.

Outcomes
 

If a Member of the Opposite Sex informs you, without prompting, of some of their Past Sexual Adventures, what should your reaction be ? Should you regard this as a sort of "Confession", to be treated with utmost Confidence ? What should the reaction be if you decide to "gently proposition" them ? And should this reaction recognise that you are in possession of Highly Toxic Information ?

It sounds like it never got awkward. It hasn't for me, but I'd love for that conversation to start back up. I thought it might after we all went out to a couple of bars, and they were pretty relaxed after we got home, but it didn't.

Were any of the women bolder or more reserved than the others talking about details?

I suppose my relationship with the person would guide my reaction.

I'm not sure I'm following what you are asking, though.

All were pretty free with the info, but my wife-to-be and her best friend Diane were definitely the ring leaders. Between the two of them, they would open the discussions, ask the questions and goad the other two on when needed. The other two, (Sorry, I'm drawing a blank on their names right now, dammit.) would often surprise us with an observation or a story occasionally as well.
All four of them were active in asking me questions or asking for my opinions and they knew I'd be truthful because my gf would have (and did, occasionally) call me out if she thought I were less than truthful. :rolleyes:

Nothing overt but...
 

Mrs Ferg, 2 sisters (both long-time married) and me chatting over vino after dinner.

Her 2 sisters would never have a really open conversation of a sexual nature although their attitudes are far more liberal today than 40 years ago.
This was a fairly low-key conversation but believe me the tone, eye contact and body language spoke volumes.

They were generally talking about how they met their respective partners, and both SIL’s said that their respective husbands were their first ever boyfriends.
They asked me if I had previous girlfriends and I said yes.
My Mrs didn’t have to say anything but one SIL asked if it bothered me that she had boyfriends before me. I said, no, I knew she had lots (emphasised) of boyfriends before she met me but if a pretty girl like her hadn’t I would probably think there was something wrong with her.
They seemed Ok with that but I detected whiff of envy on their part.

So, roughly translated
SIL1 “I’ve only fucked one guy in my life”
SIL2 “Me too”
SIL1 Ferg have you fucked other girls before our sister
Me “Yep”
SIL1 “Ferg, does it bother you that our sister has fucked loads of other guys before you?”
Me “No, that’s cool, I would have been surprised if she hadn’t”
SIL’s thinks “Damn”