The ladder of lengths, and which rung suits two
One hour, ninety minutes, two hours, three hours and the eight hour block, priced as a ladder rather than as an hourly rate multiplied out.
Five lengths exist and each has its own figure rather than being an hourly rate multiplied. For two guests with one therapist the ladder runs 360, 540, 720, 1,080 and 2,500. With a therapist each it runs 720, 1,080, 1,440, 2,160 and 5,760.
Why an hour is usually too short for two
Two people in one room take longer to settle than one person does. The first fifteen minutes go on arranging yourselves, deciding who goes first where that applies, and the room quieting down. An hour is over before any of that has paid off.
Ninety minutes as the default
For a couple on a short reunion, ninety minutes is the rung most people should be on. It absorbs the settling, it leaves the evening afterwards intact, and it forgives a body that is still on another clock. Two hours is a better evening but it wants a night with nothing scheduled after it.
Booking two different lengths across a trip
A common pattern: ninety minutes early in the visit, before either of you knows how the room feels, and two hours later once you do. Put the longer one on a night with a free morning behind it. Both are separate bookings, each confirmed in the same thread, and each carries half ahead if arranged more than a day out.