Cum swapping is when someone transfers a partner's ejaculate, or cum, from their mouth into the mouth of another person. Cum swapping often takes place during a threesome or moresome; however, it can also occur with just two people. It is similar to snowballing and is related to felching; both practices are common in pornography.
Before cum swapping, someone performs fellatio on a sexual partner. When the receiving partner cums, the giving partner collects their cum in their mouth. They then transfer that cum to the receiving partner’s mouth or to another person’s mouth.
Deep kissing is the most common way to cum swap. During an open-mouthed kiss, the giving partner can move the cum from their mouth into the mouth of the person they’re kissing. When people swap cum through kissing, the practice is sometimes called cum kissing.
Someone can also swap cum by opening their mouth and letting the cum fall into the mouth of their other sexual partner. The person receiving the cum might lie on their back with their mouth open. The giving partner can then open their mouth and let the cum fall into their partner’s waiting mouth.
Cum swapping can be a great way to feel closer to sexual partners. Sharing cum between two or more people can create an intimate bond. However, there may be a deeper reason that people feel drawn to this activity. According to the "Handbook of Psychology and Sexual Orientation", semen has great symbolic importance. It represents sexual power, strength, virility, and the successful completion of the sex act. Swapping cum can be a way to celebrate all of these positive virtues.
Historically, the term cum swapping referred to the practice of women passing semen from their mouths to other women, while snowballing or snowdropping was the equivalent for homosexual and bisexual men. However, over time all these terms became used for swapping cum, regardless of the gender or sexuality of the people practicing it.