From Zendaya in Challengers to the plays of Shakespeare, love triangles in various arrangements have long been a romantic staple.
But scientists now believe that some of these famous throuples may actually be an entirely new form of sexual attraction.
A new study from researchers at Seattle University argues that 'symbiosexual' people are attracted to the energy between established couples rather than any of the individuals themselves.
A large number of participants in the study reported feeling a sexual and romantic attraction to a 'third force' or 'synergy' between the existing members of a couple.
Dr Sally Johnston, an adjunct professor of anthropology and sociology who conducted the study, says: 'We need to rethink the nature of human attraction and desire as only one-to-one experiences.'
It might seem like sexual and romantic attraction is something that happens between two individual people -whoever you are attracted to.
However, in research published in the Archives of Sexual Behavior, Dr Johnston argues that this is not necessarily the case.
She first encountered this phenomenon while researching the treatment of 'unicorns' within polyamorous communities.
A 'unicorn' is a term usually used to describe a bisexual woman who is willing to enter into a relationship with a heterosexual couple.
While Dr Johnston found that so-called unicorns were frequently poorly treated, objectified, and ostracised, she also noted an interesting feature of their relationships.
Dr Johnston told PsyPost: 'As part of the polyamorous community, I have heard people talk openly about experiencing attraction to established couples.
'I wanted to learn more about this understudied attraction.'
In this study, Dr Johnston used data from The Pleasure Study which surveyed 373 participants about aspects of their sexual and gender identity.
Of those participants, 145 reported that they had felt a feeling of attraction to two people and their relationship together.
While this figure seems high, it is worth noting that this sample size is small and the survey participants are not representative of the wider population.
The sample skews heavily towards white, middle classes, university graduates with more than 90 per cent identifying as queer and 87.5 per cent saying they are polyamorous.
Nevertheless, in interviews with 34 of those participants, Dr Johnston claims to have found consistent evidence of a previously unstudied sexuality.
She says: 'There is a diverse population of people who experience symbiosexual attraction, an attraction to the energy, multidimensionality, and power shared between people in relationships.'
This is a distinct form of attraction to the person-to-person attraction present in some polyamorous relationships.
For example, in the films Challengers or Professor Marston And The Wonder Women, it is the mutual attraction between each of the three individuals which forms the basis of the relationship.
However, many of those interviewed reported finding themselves attracted to the energy and dynamics between the members of an established couple, rather than the individuals.
Of those surveyed, 35 per cent said they felt this attraction sometimes or often while 51 per cent said they had felt this attraction a few times.
One participant, named as Hayden, said in an interview that she was attracted to couples because of 'their cohesiveness.'
Haden added: 'You feed off their energy, their attraction to each other…there’s an interplay between the couple.'
Another participant, only named as Sage, said: 'I also just want to be smack in the middle of that relationship. I would also like to be included in this relationship… I really think my ideal dynamic might be myself and a couple'.
Asked what traits might explain their attraction, symbiosexual people said they were extroverted, wanted lots of intimacy, care, or attention, and were less likely to experience jealousy.
One participant, named Eden, said: 'I have this desire to be desired and I seek a lot of validation, a lot of validation, and when there are multiple people like that, I feel like oh, yes, yes, I’m doing things right.'
Additionally, some participants explained their attraction by reference to their 'sexual openness and queerness' and reported being more attracted to queer and non-heterosexual couples.
Going forward Dr Johnston says more research is needed to investigate the prevalence of this sexual orientation in the general public.
Additionally, further investigation will be needed to explore how symbiosexual attraction affects people's mental health and relationship satisfaction.
Dr Johnston says: 'I have a follow-up study under review examining sexual and romantic experiences with couples of people who experience symbiosexual attraction.