[M4F] You and your boyfriend convience my wife to join you in a throuple relationship - slow, romantic

My wife (Clara) and I have been married for several years. We have a great relationship and a good sex life. We are even proud to say we managed to dip our toes in exploring things with other people. A few girls joined our bed for one night stands. We want to try more but finding unicorns is extremely difficult, as you know.

The solution? We decided to also explore with couples, nothing serious, just to get to know one or two, maybe change some ideas, some experiences. That's how we met the two of you. One night on the apps we matched. Our conversations were so natural, so engaging, we just had to meet the two of you.

So we went on a date, and then another, simple, innocent get-together. We discovered that the 4 of us shared multiple hobbies (curious to explore with you what they are) and we started getting closer and closer. You always make Clara compliments, but they are always sweet enough that I don't feel a need to stop it. I agree with most.

The thing is from the start you suggested that you would really want a unicorn for yourself. And as our relationship progressed you keep making comments that you would love for Clara to join you one night. The comments were always surrounded with a good atmosphere and a pleasant discussion so it was easy to agree with them.

It's probably obvious that one evening things started becoming intimate. At first it was just between the girls, they would share a kiss, or they would start making out. I and your boyfriend would both encourage the two of you to continue or try out more.

The shyness goes away, and you try more and more. And you always find a way to be just a bit closer to your boyfriend while doing this. For instance, one time when we had a bit of a drink you girls decided to compare boobs to find out which has the nicer pair. It was that classical "you do, no, you do". Your boyfriend was the one that got to properly compare and make the final decision (wonder which pair did he prepare?).

Eventually the 3 of you would start a sexual adventure together, and the adventure would grow into more and more. It would take months or even a year before you 3 decide that you want to be a throuple.

What I would love to explore is how our relationships change over time. How is our sex life affected? What are some of the pivotal moments in this story?