Just be honest and say I have had a couple of people come to be with new students and not take the class for themselves it didn't work at all. Your friend will be dependent on you and that makes me feel uneasy all during class. For the future have the No Pay, No Stay rule printed on the sign up list. My guild had to post in big letters NO PAY NO STAY at all workshops and classes. Some thought it was just fine to sit and visit and not take the class.