I had my first male/male encounter in an MFM threesome about 40 years ago. What a surprise, when my VERY straight friend cupped my balls & stroked them while I fucked the young lady with us. The ice broke, & we spent the whole night taking turns fucking her as we stroked & sucked each other in between.
The next morning, I felt amazing, & more completely my sexual self. & I have done it many times since.