You could always sell him out. Start preaching the money game. Like dude, where is my money. And dude I need my money. Or I would like you a whole lot more if I had my money. Or I will trade you your one shoe, and this previously soiled blanket for my money. Or, I really don't want you and your girl hanging around, sexing all over the place, unless I get my money. In fact that one really is not about the money. Or, if you think our friendship is not about the money, your dead wrong, so can I please have my money. You can keep the shoe, and the girl, just give me my money. Or, I'm going to need to pimp out your girl, because I want my money. Were is my money? Are you hiding my money? Do you have anything I could actually want? A gun, a stereo, your parents jewelry? Something that is equivalent to say perhaps... money?
Is this rap?
Seriously though, I have gotten people out if my life by having them owe me money, and knowing they will never pay me back. If you want to be friends with people, that is the stuff you need to deal with. Either they like you, you are part of their supply, or both.