Not The Girlfriend Type

Cassie just graduated high school, is taking the year off from college and landed her first real job.
Mike has been working since his junior year of high school, just graduated high school and started college.
Cassie is a dedicated athlete with a hidden dark side and a no strings attached rule.
Mike is all about parties, girls and no strings attached.
They have a mutual agreement that starts as just friends and grows into more well friends with benefits. What happens when one of them starts wanting more, will they make it? or break it?