The mask embodies the spiritual power of a 'spirit' that resides in the wilderness. Often, these are mythical beings that originate from the forest and manifest themselves through the masks and their dancers/bearers, making their way among humans. Without a mask costume, however, the object has become incomplete and basically 'lifeless'. Mask and costume are inseparable, only then can the mask fulfil its role within society. Thus, although both parts are essential to the whole, often only the mask was of interest to collectors and the costume is generally lost.
Unfortunately, it is therefore impossible to determine the exact function within society purely on the basis of the shape (appearance) of this face mask. In the absence of any information about the mask costume and the context in which it occurred, we can only guess at best, although the leopard skin and mobile lower jaw do indicate a direction in which we can think.