Rub off is a variety of pigmented leather where the surface is made more attractive by the application of a contrasting topcoat, which can be partially removed (rubbed off) to reveal the underlying colour. This effect relies on a very thin top layer, which will have a more limited durability. This leather will be subject to colour change in use.
A damp cloth and a pure mild soap solution will remove most stains. Care should be taken not soak the leather. Do not use detergent. A number of proprietary leather cleaners can be purchased, for this type of leather.