Red Tantra is a personal and spiritual growth path that includes sexual energy. It is a primordial force with incredible potential; it is so powerful that it can lead to spiritual realization quickly if channeled upwards. On the other hand, sexuality does carry a strong force within human beings, which can cause them to fall into attachment quickly and become slaves of desire.
Tantra is a path that embraces life in all its forms. Even couple relationships become a practice of growth and evolution. When you are using sexual energy intensely, especially if you practice red tantra, it is not difficult to understand why the topic of polyamory (intimate relationship with several people at the same time) comes up so often.