Almost everyone and their grandma has fantasised about having a three-way. Like most sexy or kinky encounters, the more you plan, the more fun it will be. Good group sex almost never happens spontaneously without prior discussion, rules and forethought, except sometimes amongst established triad relationships. In an ideal world, you will all have a filthy, fun time, where everybody gets off and you lie with limbs entangled in a happy, spent heap at the end. In the worst case, you will have slammed doors, tears, and divorce papers.