John Marshall and Kirsten Fletcher decided to live together. They leased an apartment, each paying one-half of the rent. When he signed the lease,

Marshall was 17; shortly after signing the lease, he turned 18 and moved into the apartment. He paid his half of the rent for two months and then moved out because he and Fletcher were not getting along. Fletcher sued Marshall for one-half of the monthly rent for the remainder of the lease. Who wins? Discuss.