The rules were loosely defined, which is to say, there were none. My boyfriend and I didn’t discuss what was happening, other than a breathless, “Isn’t this incredible?” We knew the Third’s internship would end in August regardless, so why fret? There was no time to waste.
In mid-July, I realized we were falling in love. We were at a tapas restaurant downtown and the Third was telling a story from his childhood. I looked over to see my boyfriend smiling and staring intently at him. His expression was so smitten that for a moment I wanted to smack his grin away, thinking, “You don’t look at me like that anymore.” But then I blinked and realized that I was wearing the same, doofy expression.
We were both committing the same crime at the same time, so all would be forgiven, right?
Not quite. When our group chat fell silent one afternoon while they were together, I found myself running home from work early in hopes of catching them “at it.” I never did, but I began to resent their solo drives to work together. I started checking the live video feed from our dog’s treat dispenser in the living room. Jealousy was rearing its heinous little head, made even more grotesque by the guilt of knowing that I, too, craved solo time with the Third.
The geometry of a throuple is complex. With a couple, there’s only a straight line connecting two dots. But introduce a third point, and so many more possibilities emerge — only one of which is an equilateral triangle.
Although the Third slept between us in bed, sat across from us at dinner and walked between us holding both of our hands, the angles in our throuple kept shifting.
One afternoon, I discovered that my boyfriend had bought the Third a new pair of cycling shoes. It was a shallow cut, sure, but it proved, for me, a shared impulse to reel the Third closer to our own respective sides of the triangle. Not to mention: Where were my shoes?