If your son or daughter is dating or thinking about dating, you need to make sure he or she understands the dangers of a "risky threesome." A risky threesome is when two women are involved in a relationship with three or more men. A risky threesome is considered a trifecta, which is a group that has a higher incidence than any other in regards to gang-related crime, including sexual assault. So if your son or daughter is thinking of or is dating a girl who might be a trifecta, you need to let him know the risks involved..