How do I get this guy to drop weight now?

Oh, and again it's mainly his idea. I told him he didn't have to fight. I quit boxing for a while, and thought I'd try to train some people a little bit to keep active in it, and use the mits to keep my reflexes sharper. Somethin to do...
This kids the one that wanted to fight cuz he has something to prove so thought I'd teach him as much as possible to give him a better shot of success. I don't think he's at a big risk of getting seriously hurt..Unless of course like you say he dehydrates the **** out of himself for the fight.