The book Alchemical Sex by E.J. Gold, explores the esoteric practice of using sexual energy for spiritual transformation.

The text details a system of inner alchemy, viewing the human body as an alchemical laboratory capable of producing higher substances. It emphasizes impartial self-observation and discipline to control the "human biological machine" and achieve longevity. Tantric practices and the invocation of entities are central components, requiring harmonious centrums and the transcendence of romantic love.

The book also examines the historical context of similar practices in various cultures, including harems and Tantric clusters, while cautioning against the dangers of entities and contamination.