what is a rainbow kiss (https://www.cupidbaba.com/rainbow-kiss/) meaning A rainbow kiss happens when one partner performs oral sex during menstruation, while the other partner performs oral sex at the same time. Their fluids mix during kissing. To do it safely, always discuss consent and comfort first. Use dental dams or condoms to reduce risks of STIs or infections. Maintain good hygiene, avoid if either has open sores, and ensure both partners feel safe and comfortable.