I [M] found out my (half) brother and sister-in-law [F] are swingers

So this just happened yesterday, and I have no one to tell, so hello internet: I had my half-brother, Rob (33m), and his wife, Alexis (27f) over for a little family lunch yesterday. They just had a baby 4 months ago, and I wanted to wait until I was fully vaccinated to see them, and after my two week post-shot time was up, here we are at today.

A little backstory: Rob and I had the same dad. Both our mothers passed away about a decade apart from each other in ’97 and ’06, and our dad passed in ’09 ago due to natural causes, and since then we’ve made it a point to keep in touch more often. We’re not super close, and we have conflicting personalities. He’s kind of a Frat-type douche bro who’s super self-absorbed, and I’ve always been the level-headed more down to earth one. When shit in his life goes wrong, since our dad died, he bitches to me, and being 6 years older than him, I tend to handle his shit for him. His wife knows this, and she sees me as the great mediator for all situations. Her and I have always had this kind of odd friendship because we’re really much alike, with the same sets of interests and such.