Hey! I Actually Need Opnion On This Matter. My Friend

Hey! I actually need opnion on this matter. My friend has fetish of eating human toes which are thoughts that he has now and then and I have helped him by role playing in different situations that helped him controlling but I want a solution for this so that he can be free these thoughts he has like eating girls toes and legs. What do I do to make him forget these thoughts or get rid of it and most of all, am I doing right thing by helping him? Is it right ?