The majority of my mature years were spent with a partner 13 years younger than me and, funnily enough, he was my Pokemon platypus. But only as a joke. Even Beanie Babies don't feel like mine even with that, and selling them in Harvard Square, and collecting my real (vs person) ones. They're all different generations.
We never called it anything other than poly or open or cheating or what have you. Or is my memory so shot I can't remember what it was we called our version of Hazel Wassername. Sociopath? Sure. But seriously. What did those of us in the 40-50 age bracket call the "Walk of Shame"/"Stride of Pride?"
I'm currently exhausted and this mind game isn't helping me cope with my stress induced insomnia. Sun is up. Time to sleep.