Both are worked with the whole body rather than the hands, so the two names get used as though they were interchangeable. They are not. The difference is the material, and the material changes almost everything downstream of it.
The two get confused for a reasonable reason. Both abandon the hands as the primary instrument, both bring the therapist's forearms, torso and weight into the work, and both look, described in a sentence, like the same idea. The difference is not in the intention. It is in what is between the two bodies, and that single variable changes the pressure, the pace, the length of the stroke, the temperature of the room and what has to be put down on the bed first.
A body-to-body massage is built on oil, and oil permits contact without removing friction. There is still grip. The therapist can hold a position, apply pressure to one point and stay there, take a long slow pass down the back and then stop at the base of it, and the stopping is part of the shape of the thing. Oil-based work has punctuation. It has strokes with beginnings and ends, and it has moments of stillness that read as stillness precisely because the previous movement could be felt to finish.
That makes body-to-body more adaptable than people credit. It can be firm or it can be almost weightless. It survives a cool room better, it survives a narrow bed better, and it can be folded into a session that starts as ordinary massage and becomes something else halfway through. An hour is a coherent length for it.
Put the gel in and the grip goes. Nothing catches, so nothing can be held, and a therapist cannot stay in one place by pressing harder — pressing harder in gel just means sliding further. What replaces grip is weight, applied by leaning, and what replaces punctuation is continuity. The stroke has no natural end. One movement runs into the next without a seam, and the absence of a seam is not a stylistic flourish; it is the mechanism. The nervous system loses track of where it is being touched because the touch never stops long enough to be located.
That is why the two feel so different from inside. Body-to-body is felt as a sequence of things happening. Nuru is felt as a single continuous event of variable pressure, and afterwards people tend to describe it less as a massage than as a temperature.
Neither is a more advanced version of the other, which is how the pairing is usually sold. They are built on opposite principles. One uses friction carefully; the other removes it and works with what is left. Both are on the same rate — an hour is 180, ninety minutes 270, two hours 360 — so the choice is never a question of budget, only of which of the two you actually want.
If you have had one and are considering the other, the useful question is not which is better but which principle appeals. People who liked the clarity and the pressure of body-to-body sometimes find nuru too undifferentiated. People who found ordinary massage a series of interruptions tend to find in nuru the thing they were describing when they complained about that.