My boyfriend told me he has a fat and says I have to gain 100 pounds or he'll dump me. What should I do

I really like him and we have been going out for a month but yesterday he told me that my body doesn't turn him on anymore and that he wants me to look like Rosie O'donnel. I like him a lot but do you think I really should put on 100 pounds just to stay with him. Help me out please.