Yoni is the Sanskrit word for the vagina that is loosely translated as "sacred space" or "Sacred Temple." In Tantra, the Yoni is seen from a perspective of love and respect.
The goal of the Tantric Yoni massage is not solely to achieve orgasm, although orgasm is often a pleasant and welcome side effect. The goal can be as simple as to pleasure and massage the Yoni. From this perspective both receiver and giver can relax, and do not have to worry about achieving any particular goal. When orgasm does occur it is usually more expanded, more intense and more satisfying. It is also helpful for the giver to not expect anything in return, but simply allow the receiver to enjoy the massage and to relax into herself.