Priscilla can pinpoint the moment she realized her throuple was falling apart. Her fiancée, Kiara, had started kissing their shared girlfriend, Olivia, in a way that lingered too long. One night, after a romantic dinner in Savannah, Georgia, the three of them returned to the car, and Olivia and Kiara began kissing in the front seats, seemingly oblivious to time. About ten minutes in, Priscilla tried to reach out and touch her fiancée’s shoulder, but her seatbelt was buckled. Unbuckling and leaning forward felt intrusive, and anyway, Kiara and Olivia seemed to have forgotten about her. Watching the kiss from the back seat, surrounded by baby seats and toys, Priscilla thought about how by rights it was her turn to sit up front. She felt a flicker of competitiveness. "I worried, am I desired less than her?" she recalls now. "Will I be replaced?"
In the early days, Priscilla felt giddy with excitement. She and Kiara had been together for eight years, and adding a third person felt like a way to explore non-monogamy without losing each other, because every new romantic experience would be shared. Olivia was an old friend, so Priscilla and Kiara’s children were comfortable with her. When the kids were in bed, they would walk to the beach holding hands as a trio to watch the sunset. At night, they would curl up and form a cuddle chain: Priscilla cuddling Olivia, and Olivia cuddling Kiara.
Sometimes Priscilla would wake up alone on one side of the bed and see Kiara and Olivia cuddling without her—at first this didn’t bother her. "I felt a little left out, but I was happy that Kiara was happy," she says. The problems began when both Priscilla and Kiara moved beyond lust and fell deeply in love with Olivia. "The thing about throuples is that when real emotions get involved, things get more complicated."
In a throuple, three people commit to forming a romantic unit together—like a couple, but with an extra person. In other forms of non-monogamy, you might have multiple partners, but typically only sleep with one at a time. Throuples are different: they date, have sex, and sometimes raise children as a three.
In Britain, 9% of adults are open to polyamory, according to a recent poll, and while no official data exists on throuples, they seem to be on the rise. In 2017, three men in Colombia became the first throuple to form a legal union. Earlier this year, author Lindy West released a memoir about falling in love with her husband’s mistress, and the three now live together. Many cities in the US now have protections against discrimination for polyamorous people.
The throuple has moved from curiosity to mainstream visibility. Films like Passages (2023) and Challengers (2024) explore experimenting with a third partner. In the HBO show DTF St Louis, David Harbour plays a man who tries to develop sexual feelings for his wife’s lover to live as a three. But there is also backlash: younger generations seem to reject polyamory, with 81% of Gen Z fantasizing about monogamy.
Being happily polyamorous requires patience and thoughtfulness, but throupledom demands even greater emotional maturity. Managing the desires and insecurities of three people is a feat, and even within poly circles, throuples have a reputation for being fraught. In The Ethical Slut, the authors warn that lovers often compete for affection like siblings.
With about 42% of marriages ending in divorce in Britain, one could argue that coupledom has been a failed experiment. But what really happens when you settle down as a three? I spent six months talking to people in throuples that went spectacularly wrong—and some that are thriving—to understand how to manage infighting and rivalry. How do you make a throuple work? And what happens when it implodes?
In The Ethical Slut, the authors write that in any ménage à trois, there are actually three couples: A&B, B&C, and C&A. What makes the throuple unstable is that at any time, the mini-couples can become more estranged or entwined. In Priscilla’s throuple, it was initially Priscilla and Olivia who were closer—Kiara felt left out. Early on, Kiara discovered that Priscilla and Olivia had sex while she was at work. That wasn’t technically against the rules, Kiara tells me, but "it was very hurtful and broke a lot of trust."