Why even work part-time?  You&#x27;re not getting paid.  Tell them you need more equity and that your co-founder needs to focus on the business instead of on his personal image.  When they say no, just leave completely (no part-time work unless you&#x27;re actually paid for it) and go back to school.  If they want you to build their company for them—and it is <i>their</i> company if you only have 10%—they need to compensate you properly.