Professor told me to organize a lecture course I am a PhD candidate. My advisor told me to make and organize a lecture course, for which he is formally listed as the instructor, but he has little knowledge about what the lecture course will deal with. I have more knowledge than him.

Students attend class two times per week. 


One day, they give presentation about paper reviews related with this course. 
The other day, I conduct the class and give them knowledge in order to understand papers. In both days in a week, he does nothing.


I don't think it's normal. 

Even though he gives me many thanks for conducting the class, my feeling isn't going well. Even worse, I don't get paid.

However, because of a (de-facto) vertical relationship between him and me, I don't know what should I do. 

I am not sure an ethics committee can protect my privacy.
Main thing here is that you provide work that is not paid.

(Assumption: studying and working in academia is not volunteering or philanthropy. Not quite clear what culture would have to do here. If you feel wrong about the situation, seems that you agree with this assumption, and you're not confusing exploitative situations for real opportunities.)

If that's an opportunity that's offered to you, the local unit/department/centre/faculty ought to offer remuneration for the work you provide, either for preparation work only, or for both preparation and delivery. In other words, the staff member should (have) arrange(d) the practical and financial details for the opportunity.

A 'research ethic committee' has little to nothing to do with the situation you describe, as the situation does not relate to your doctoral research activity. The situation is not about research ethics, it's about professional ethics.

Have you talked to your local administrators/support staff to enquire informally about the affluence of the local unit? Simply, is there money somewhere to cover for the work you contribute? Can they afford to provide you a remuneration that is a fair reflection of the work you provide?

Have you talked to your head of department about the situation? Colleagues might not be aware of the situation, and might disapprove, and help you out, of it.

Last but not least, are there union reps on your campus that you could approach for informed advice?