A couples massage is not really different than a massage for a single person, except it is in a larger room with two massage tables, two massage therapists and a client on each table. The one thing that one might not do is one client is getting a hot stone massage or (airborne) aromatherapy and the other is not, for such might negatively affect the other client and/or therapist due to the aroma (allergies or worse?) or the heat from the stones. Hence, it is best if both clients are getting the same kind of session (Swedish, deep tissue, etc).