Unicorns

What is a unicorn some may ask? Beyond being a beautiful mythical creature it is also the term that is sometimes used in poly circles to describe a single person, who is looking to join a couple for sexual play, is expected to pay equal attention to each member of the couple and have no string attached.
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While for some, the term “unicorn” is seen as a playful and fun label, others view it as dehumanizing and derogatory. Especially through the lens of “unicorn hunters”. .
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“Unicorn hunters” which most, if not all, tend to associate a negative connotation with. This is in reference to the couple that is looking for the third (typically an attractive bisexual female). The reason for this is that this might lead to the third being used as a sexual prop rather than a third person with wants and needs. Furthering this, the couple often holds the privilege, in terms of dictating rules and boundaries, leaving the unicorn with little say.
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Of course, it is always possible to add a third (regardless of gender) in a respectful, mutually beneficial fashion but then are the terms “unicorn” and “unicorn hunters” helpful in reaching that dynamic? Does language matter? What are your thoughts?