No.
oh wait, i just realized i talk about joining a asian club in one of my supplementals…so ru sure it wont hurt me if i leave this blank?
Not at all. Officially, they are just keeping track of the makeup of the college. Besides, what’s the worst case scenario - that they assume that you are Asian? How does that differ from if you marked that you are Asian?
So don’t worry about it - not marking anything will have absolutely zero effect on your admission as opposed to checking that you are Asian.