Merge5 is one of the drugs available in Bay City. Takeshi Kovacs bought Merge5, along with a large number of other drugs, from a street dealer. A biochemical pheromone designed to "put bodies in touch with one another", causing strong sexual arousal and enhanced physical sensations. A stronger form of this pheromone is called Merge9 which can be designed within clone bodies, produced within their bodily fluids like sweat and saliva when the body experiences arousal. Many prostitutes and synths use merge5 to attract customers.