Ryan is a young Generation X’er, while she’s an older Millennial.While both generations were raised by Baby Boomers – who not only initiated the sexual revolution, making acceptable the concept of sex outside the confines of marriage, but who then went on to mostly pair off in traditional marriages – hers was the generation in which the greatest percentage of those partnerships ended in divorce (the divorce rate peaked in the early Eighties, right around the time it’s believed that the Millennial generation began).

Once Ryan learned that a permanently open relationship was what Leah wanted, he says, “There was a side of me that was ecstatic – the teenage boy in me that wants to fuck everything I see.

But the other side of me was concerned about what this means in terms of intimacy and how the dynamics would work. It’s skirt day.” Kristina is wearing long, soft curls, dark crimson lipstick, a black shirt that’s open in the back and a sequiny green miniskirt over bare legs.

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“I remember the first night, I was telling him about my difficulty with monogamy,” she says.

“I don’t know why I felt the need, but it must have been on my mind a lot.” In almost every relationship she’d had, she’d found herself cheating, though she didn’t know if this was a character flaw or a problem with the conventional system. “I was just trying to get into your panties,” he says to her, laughing.

In other words, Leah’s is a generation that has been raised with the concept of sexual freedom and without solid guidelines for how to make monogamy work.

That some brand of non-monogamy would appeal to large numbers of them is thus unsurprising.

He was therefore surprised when the first thing Leah gave him after the move was a book called Certainly, open heterosexual relationships are nothing new.

Even the term “open relationship” seems like a throwback, uncomfortably reminiscent of free-love hippies, greasy swingers and a general loucheness so overt as to seem almost kitsch.

Or, more specifically, that going outside the partnership for sex does not necessitate a forfeiture of it.