Quartet

A quartet refers to a sexual constellation involving four people, usually two couples engaging in sexual contact with one another. It often involves partner swapping, but the term can also refer more generally to group sex with four participants. It is sometimes used in swinger contexts.

As with any sexual encounter, consent, clear communication, and respect for boundaries are essential. For the safety of everyone involved, safer-sex rules and respectful behavior should be discussed in advance. Pressure, jealousy, or unspoken expectations can quickly strain such situations.