The swinging community hid in the shadows. Then came #SwingTok.

Krystina loves pineapples. Not just because of how they taste but because of what they represent.

Pineapples – upside-down pineapples, specifically – serve as a signal: that you and your partner are swingers.

Don't believe us? Head over to #SwingTok. Pineapples are plentiful on social media app TikTok across the hashtag, which has amassed more than 582 million views.

Krystina, 38, who requested her last name be withheld due to recent harassment she's received, blossomed into a #SwingTok influencer earlier this year after revealing herself to be a swinger on the platform. She and fellow swingers have forged a community on TikTok, and hope to demystify swinging and curb judgment from skeptics.

"I want people to know I'm a swinger," says the hairstylist from Michigan. "I'm proud of it."

But what exactly is swinging? How is it different from other non-monogamous relationships, such as open relationships or polyamory?

"Non-monogamous relationships can be as fulfilling and rewarding as monogamous relationships," says Cecille Ahrens, a licensed clinical social worker at Transcend Therapy in California. "One is not necessarily better than the other."

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What is swinging?

Swinging usually means exchanging partners strictly for sex, according to a 2014 article in the Electronic Journal of Human Sexuality.

"Spouse exchange" has indeed happened historically, and as recent as the 1940s, nearly 40% of the world accepted it culturally. "Key clubs" in the U.S. included WWII fighter pilots and their wives, later dubbed "wife-swapping" in the 1950s. It's unclear how many partake in swinging – some estimates say 2% or less – though one study from the North American Swing Club Alliance said 15% of U.S. couples have tried it at least once in their married lives.

Nowadays, people visit swinging clubs and can otherwise connect online with other swingers.

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Typically, swinging is "fairly white, middle to upper class, and cisgender-focused, while other different versions (of consensual non-monogamy) tend to be practiced in more diverse ways," says Shanna Katari, an assistant professor at the University of Michigan's School of Social Work and Department of Women and Gender Studies.

As shown on #SwingTok, the practice works for many couples – and hundreds of millions of people are at least curious enough about it to watch videos about swinging online.

"There's no competition, there's no jealousy. We both get to do what we want to do," says swinger Kylie George, of Cleveland, Ohio.

How do you know it's for you? "Opening up a relationship works best when the relationship as it is feels stable, honest, and communicative," says Allison Moon, author of "Getting It: A Guide to Hot, Healthy Hookups and Shame-Free Sex." "Swinging won’t fix a broken relationship, but it can add new adventure and excitement to already solid ones."

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The evolution of #SwingTok

Monogamy never felt like a fit for Krystina – even as far back as her first boyfriend in the fifth grade. She always dated multiple boyfriends, always cheated.

That continued after marrying her husband; before they began officially swinging with men, too, she cheated on her husband. The pair had always been sexually adventurous with other women.

"I just didn't know how to explain to him that I only am in love with him," she says.

"I only want to spend forever with him, but I still want attention from other men and I want to sexually be with other men."

By fall 2019, they researched swinging and met their first couple.

She began posting videos about her marriage in late 2020, but she wasn't quite ready to reveal they were swingers. But after seeing another swinger post about it, she wanted to join the fun and educate people. #SwingTok eventually trended – and true community was born.

"We're not just these sex-crazed maniacs," she says. "We love to have genuine friendships with people, and it's like a friends-with-benefit thing and swinging community is the only community I've ever felt accepted in my whole life."

Kylie George was a part of TikTok previously, mainly focusing on body positivity before joining #SwingTok. But meeting other swingers doesn't guarantee she and her partner will indeed swing with them.

"In the swinging community, you've got to be a little picky about who you swing with," she says. "I don't just swing with everybody."

The #SwingTok creators run a Discord chat together and have plans to collaborate through TikTok and adult websites; they also hope to create a swinging app.

"We want to break the swinger stigma," she says. "We want people to know this is not weird. This is not crazy. This is something that is normal and normal people with normal jobs do this."

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The differences between polyamory and swinging

The biggest difference between the two? Polyamory is not just about sex. Polyamory means "multiple loves."

An easy way to tell the difference on social media (and in real life): pay attention to the pineapples. "On cruise ships, on your mailbox, on your Facebook, interested parties can put (up an) upside-down pineapple," says Niki Davis-Fainbloom, a New York City sex educator. "It is a subtle way to attract like-minded individuals without being that awkward couple who always asks their friends to have sex with them."

George has everything pineapple around her house. "My partner always says, 'You're not being very subtle about it.' And I say, 'I know. I'm not trying to be.'"

Leanne Yau, who is polyamorous, never felt comfortable with monogamy – and ultimately founded non-monogamy social media platform Poly Philia. She explains the nuances and potential for overlap between the swinging and polyamory communities: "A lot of polyamorous people do participate in group sex and go to swinging parties and that kind of thing and similarly, there are some swingers who have developed long-term relationships with other couples which may not be explicitly romantic but they are committed and could look like polyamory."

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Those on #SwingTok want you to understand

► There's a stigma. "I don’t think we can expect it to be at the level of respect and high regard as marriage, at least not for a long time," Ahrens says.

► Couples therapy is a useful tool. "It is really important to set parameters and boundaries up front. It is also important to build shared language, to talk about how you would navigate certain circumstances, and more," says Moe A. Brown, a licensed marriage and family therapist.

► Communication plays a huge part in a healthy relationship. "The most successful open relationships are the ones that talk a lot about what’s going on for them," Moon says.

► Jealousy is inevitable. Think about it like a "check engine" light in your car, Moon says. It happens and is not inherently wrong. "It doesn’t mean that your car is toast, or that you need to pull over right away and light the thing on fire. It doesn’t mean you should’ve never bought the car in the first place. It’s just an indicator light that something needs to be looked at."

► There are lots of options for those interested in trying out an open relationship. "Swinging may be one of the best-known flavors of open relationships, but it’s not the only one," Moon says. "Ask yourself, what kinds of relationships do I want with the people I sleep with? What kind of sex am I looking for? How important is an emotional connection to my sense of sexual satisfaction and pleasure?"

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This article originally appeared on USA TODAY: Pineapples sign of swinging community on Tiktok, but who are swingers?