What Is a Unicorn in a Relationship? Unicorns, Bulls and Fair Play

A unicorn in a relationship is a single person, most often a bisexual woman, who joins an existing couple as a third partner. The word appears in polyamory, swinging and dating apps, and it usually means someone who dates both members of the couple. Its cousin, the bull, is a man a couple invites to be sexual with one partner while the other partner agrees, often in hotwife or cuckold play.

Both words are simple to define. The harder questions are about fairness, feelings and health. This guide explains what each term means, why “unicorn hunting” draws so much criticism, and how people set agreements, handle jealousy and plan STI testing when someone new joins.

What a unicorn means in non-monogamy

The usual picture: a third who joins a couple

In most conversations, a unicorn is a single person who is open to dating both people in an established couple. The result might be a triad, where all three are partners, or something more casual. The classic image is a bisexual woman joining a man and a woman. That picture is common enough that many people treat it as the definition.

Unicorns are part of consensual non-monogamy, or CNM. That umbrella term covers relationships where everyone agrees that partners can be romantic or sexual with other people. It is less rare than many people assume. US studies summarized by psychologist Amy Moors suggest that about one in five adults have tried some form of open relationship or CNM at some point. US survey data put the share currently in such a relationship at around 5%.

Why people call it a unicorn

The name is a joke about rarity. To a couple searching for one, such a person can seem as rare as the animal in the myth. A dating guide from DateBeyond adds that couples often picture someone available, emotionally grounded and interested in both partners. Each extra wish makes that person harder to find.

Plenty of bisexual women happily call themselves unicorns. One former unicorn warns that the label can also make newcomers easier for unicorn hunters to spot.

Can a man be a unicorn?

Yes. The traditional meaning leans toward bisexual women, but men and non-binary people take the role too. A man who joins a couple is sometimes called a dragon instead, though the slang shifts from one community to the next. Gay, lesbian and queer couples can also look for a third. The role is defined by the shape of the relationship, whatever the genders involved.

What unicorn hunting is and why it gets criticized

Unicorn hunting is when a couple searches for a third who will date both of them, date no one else, and follow rules the couple wrote before meeting her. Critics say the setup can treat the third as an add-on instead of a person starting two real relationships. Wanting a triad is fine in itself. A former unicorn writing on Polyamory For Us makes the point plainly. A couple that only wants to date a bi woman together is narrowing its options, which is not the same as doing harm.

Rules couples often bring

The trouble usually starts with the rule list. Writers in poly communities point to the same handful again and again:

• “We come first.” The couple stays primary and the newcomer is secondary, decided before she arrives.
• “You have to love us both equally.” Feelings rarely grow at the same speed with two people.
• “Only together.” She may not spend time alone with either partner, while the couple keeps its own private time.
• “If she doesn’t like the rules, she can leave.” Her say is limited to taking it or walking away.

Writing from her own time as a unicorn, the author of Polyamory For Us says the couples she met were usually new to non-monogamy rather than malicious. The rules come from fear of losing what they have.

Why critics call it unfair

The core problem is power. Two people who already share a home, history and plans set terms for one person who has none of that. Polyphilia describes couples who push the third out whenever their own relationship gets rocky. That leaves her the most exposed person in the arrangement, with the least say.

Wording matters too. Phrases like adding “a female” to a relationship suggest she will be fitted into an existing shape. The “only together” rule also creates a double standard, and it can turn into resentment once the novelty fades.

What a fairer version looks like

A triad is really four relationships: each pair, plus the three together. Each one needs its own care. A fairer approach gives the third an equal voice in how things grow, lets bonds form at their own pace, and drops any veto over her feelings.

Couples should also expect change. Opening a relationship changes it for good, so rules meant to freeze the original couple tend to hurt every relationship involved. DateBeyond frames the healthy version as inviting rather than hunting: being honest about what you want and treating the other person as a whole human being.

What a bull means in swinging and hotwifing

The bull in a hotwife or cuckold dynamic

A bull is usually a single man who becomes sexually involved with one partner in a committed couple, on terms the couple has agreed. The word shows up most in hotwife and cuckold arrangements, and in swinging more broadly.

Those two arrangements overlap but feel different. Men’s Health describes a hotwife as a woman whose partner has given his blessing for her to see other men, for the pleasure of both of them. He may watch, or he may simply hear about it later. In cuckolding, watching or listening is central, and the scene often plays with power or humiliation. The bull is the outside man in either case. Because “cuckold” was long an insult for a deceived husband, some couples prefer other words.

Gender roles are looser than the slang suggests. The Gender & Sexuality Therapy Center notes that the bull can be any gender, and so can the partner who watches.

What makes a bull respectful

A good bull works inside the couple’s rules and does not try to rewrite them mid-encounter. He stays discreet and leaves when the arrangement ends. Before anything happens, everyone should agree on consent, STI status, aftercare and hard and soft boundaries, according to the Gender & Sexuality Therapy Center. A hard boundary might be that a condom is always used.

Is it a healthy fantasy?

It can be, when everyone involved consents and the fantasy is talked through first. It is also common. In a survey of 4,175 Americans, sex researcher Justin Lehmiller found that 52% of heterosexual men and 26% of heterosexual women had fantasized about watching a partner with someone else. Fantasies about having sex with someone else while a partner watches were common too: 50% of heterosexual men and 40% of heterosexual women.

What separates the practice from cheating is consent. In real cuckolding play, everyone agrees and no one is actually deceived, whatever the fantasy acts out. Therapists also suggest trying the idea in talk or fantasy first, before inviting a real person in.

Unicorn, bull, stag and other lifestyle terms compared

These words get mixed up because several describe an outside person joining a couple. The table sorts them by who they describe and where you are likely to see them. Meanings drift between communities, so treat it as a guide and ask what someone means.

Swingers are people in committed relationships who have sex with other couples or individuals, and much of this vocabulary comes from their spaces. Rules differ by venue, and some swing clubs do not admit single men at all.

Setting agreements before anyone new joins

Agree on the basics as a couple first, then work out the rest with the new person, not on their behalf. People in consensually non-monogamous relationships settle their terms ahead of time, which is one of the clearest lines between CNM and cheating.

Talk as a couple before you look

Start with why you want this. Is it curiosity, a shared fantasy, or a wish for more connection? Be honest about how stable your relationship feels right now. Psychology Today’s summary of Amy Moors’ research notes that people rarely open a relationship to fix it, and a troubled relationship tends to carry its problems into new ones.

Then name your limits, and talk about what happens if feelings grow. Couples hunting for a unicorn often skip that last question. It is the one most likely to come up.

Give the new partner an equal voice

The third person has needs, limits and a right to say no at any point. A therapist writing for the Institute for Relational Intimacy prefers the word “agreements” to “rules,” partly because rules sound set in stone. The difference matters here. Rules tend to get handed down, while agreements are made together by everyone they affect.

Consent also covers each encounter, not only the first conversation. Anyone can pause or change their mind, including the bull, the unicorn and either member of the couple.

Check in and renegotiate

Agreements go stale. The same therapist recommends an ongoing, open conversation about them, because life changes what people need. Agreements also break when someone agrees to a term they already know they cannot keep, just to avoid a fight. A simple habit helps: a short check-in after each new experience, with no blame attached.

Plan the exit too. Decide how anyone can pause or end the arrangement, and how you will treat each other if it does end. That plan protects the person with the least power most of all, which is often the newcomer.

Handling jealousy and compersion

Yes, jealousy is normal, even in relationships where everyone agreed to see other people. No set of agreements can stop it completely, as the Institute for Relational Intimacy points out.

Jealousy is common, not a failure

People often expect open relationships to be full of jealousy. The research is more reassuring. Studies reviewed in In-Mind Magazine found that people in consensually non-monogamous relationships report fairly high trust, honesty and satisfaction, and fairly low jealousy. Low is not zero, though. A pang when your partner texts the unicorn or books a night with a bull is ordinary.

Jealousy often points at a need. It might be reassurance, time together, or a clearer sense of where you stand. Treat it as information to talk about, rather than proof that the arrangement is doomed.

Compersion and practical coping

Compersion is the feeling of joy in a partner’s joy, including their happiness with someone else. Some people describe it as the opposite of jealousy. It is real, but Expansive Therapy cautions that it comes and goes, and someone may feel it one day and jealousy the next. It tends to grow from a secure foundation, so it is a poor thing to demand of yourself on day one.

Practical steps help more than forcing a good mood:

• Name the feeling out loud to your partner, without blame.
• Ask for one specific thing, such as a call afterward or a date night that week.
• Slow down or pause new experiences until the feeling settles.
• Build skills for calming yourself and talking through hard emotions, which therapists suggest instead of piling on rules.

Pushing hard feelings away rarely works. They tend to linger and create distance later, so naming them early is the kinder choice.

STI testing and safer sex with new partners

Adding a partner adds sexual health risk for everyone in the network, so testing and protection belong in the first conversation. The good news is that people in open arrangements tend to take this seriously. Research summarized by In-Mind Magazine found that people who cheated were less likely than people in CNM to use condoms, tell their partner, or get tested.

Testing before and between partners

Many STIs cause no symptoms, so feeling fine does not mean you are clear, the CDC warns. Testing before a new partner joins, and sharing recent results, gives everyone a starting point. Keep in mind that a test taken too soon after a new exposure can miss an infection, so ask how long to wait and when to retest.

How often to test depends on your age, sexual history and practices. The CDC says everyone ages 13 to 64 should have at least one HIV test. Sexually active women under 25 should be tested for chlamydia and gonorrhea every year, as should some older women with new or multiple partners. For men who have sex with men at increased risk, including when they or their partners have multiple partners, CDC screening guidance supports testing every 3 to 6 months. Anyone else with several partners should ask a clinician how often to test, based on their own risk.

Two details are easy to miss. If you have oral or anal sex, the CDC suggests asking your provider about throat and rectal testing options. And testing does not have to be awkward: self-test and mail-in kits exist, and many clinics offer free or low-cost confidential testing.

Barriers, vaccines and PrEP

Most condoms are highly effective against HIV and infections like gonorrhea and chlamydia, according to the International Association of Providers of AIDS Care. They protect less against infections spread by skin contact, such as HPV, herpes and syphilis. Latex offers the best HIV protection, and a new condom is needed each time.

PrEP is a medicine, taken as pills or shots, that greatly reduces the chance of getting HIV from sex. It does not prevent other STIs, so the CDC still points to condoms for those. Ask a clinician about vaccines too, such as those for HPV and hepatitis B.

Put the health plan into your agreements. That includes which barriers you use with whom, how often everyone tests, and how you will tell each other about a positive result.

Frequently asked questions

What does it mean to be someone’s unicorn?

Being someone’s unicorn usually means you are the single third partner who dates both people in their couple. The relationship can be casual or committed. Some arrangements stay light, while others grow into long-term triads. Either way, you should have your own say in the rules, and you can renegotiate or leave at any point.

What is a dragon in dating?

In swinging, a dragon usually means a single bisexual man who plays with couples. Some people use it more loosely for any man who joins a couple, much like a male unicorn. Usage varies between communities, so it helps to ask what a profile means by it.

What does it mean when someone is called a bull?

Calling someone a bull usually means he is the outside man a couple invites in, most often in hotwife or cuckold play. He is with one partner while the other agrees, and sometimes watches. A good bull respects the couple’s agreements, stays discreet and steps back when the arrangement ends.

Is being a bull the same as being a third?

Not quite. “Third” is a loose word for any extra partner, casual or committed. A bull is a specific kind of third, defined by the couple’s structure. He joins on their terms, usually with one partner, and he is not expected to become a lasting fixture in their lives.

The bottom line

A unicorn is a third partner, often a bisexual woman, who dates both people in a couple. A bull is a partner, usually a man, whom a couple invites to be with one partner, often in hotwife or cuckold play. Both roles can be part of a healthy, consensual relationship.

What makes the difference is how people treat each other. Give the newcomer a real voice, write agreements together and revisit them often. Expect some jealousy and talk about it early. Test regularly, use barriers, and ask a clinician about PrEP and vaccines. When everyone has a say, nobody needs to be hunted.

Related reading

• What Is Group Sex? Terms, Consent, and Safer-Sex Basics
• What Is Casual Sex? Expectations, Boundaries, Consent and Safer Sex
• What Is Bareback Sex? Meaning, Risks and How People Lower Them
• What Is a Sex-Positive Relationship?

Sources

1. Unicorn: Meaning & Definition | LGBTQ+ Glossary - The Gaygency
2. What Is a Hotwife? Sex Experts Explain Hotwifing (and Cuckolding) - Men’s Health
3. The Facts About Consensual Non-Monogamy - Psychology Today (David Ludden, PhD)
4. When loving hurts: The pervasiveness of stigma towards consensual non-monogamy - In-Mind Magazine
5. Unicorning: The Complete Guide to Being (or Finding) a Unicorn - DateBeyond
6. To Unicorns, From an Ex-Unicorn - Polyamory For Us (Jesse Dagger)
7. So You Want To Be A Unicorn: A Guide to Dating Polyamorous Couples - Polyphilia
8. What Is a Bull? Relationship Slang and Real Definition - VEX (dating app blog)
9. Swinger explains difference between a ‘dragon’ and a ‘bull’ in the sexual lifestyle - LADbible
10. 9 Myths About Cuckolding - Gender & Sexuality Therapy Center (Jesse Kahn)
11. How Many Women Fantasize About Cuckolding? - Sex and Psychology (Justin Lehmiller, PhD)
12. Consensual non-monogamy: Table for more than two, please - In-Mind Magazine
13. Why Making Rules Isn’t the Best Way to Start an Open Relationship - Institute for Relational Intimacy
14. Compersion in Ethical Non-Monogamy - Expansive Therapy
15. Getting Tested for STIs - Centers for Disease Control and Prevention
16. STI Screening Recommendations - Centers for Disease Control and Prevention
17. Condoms - International Association of Providers of AIDS Care
18. Preventing HIV with PrEP - Centers for Disease Control and Prevention