You conclude your question asking us for a reference to an organization that will help you if you refuse to clean up what you say is my cubbyhole. And you call it a plight. A plight is a circumstance of a dangerous or complicated nature. Doing a little cleaning around the office is neither, and it could give you a little variation from your clerical assignments. The only organization I know that might come to your aid is a union, if you have such.
Unions are good at defending individuals who are assigned jobs outside their job description.
If you have no union, only you can speak up to your supervisor. Please do not order me to. Then see what your super says. Also think ahead a bit. If there are others who are making a mess after you have cleaned, speak up.