Robert Marshall is happy in love, and because of his storybook romance with Maria Rivera, no problem in his life can bring him down. Sure, Maria's uptight mother is kind of a racist douche, his own mother is nagging him about marriage and grandkids, his ancient car is on its last wheel, and he's still paying off his college loans. But he has a great job working as a video game programmer, a loyal crew of friends who share his love for role-play games, and a fantastically healthy sex life. Nothing could ruin his perfect life, until Maria's little sister returned home from St. Vincent's.
Maria thought she was doing a good thing by introducing her nerdy sister Tina to Robert and his friends. His gaming group granted Tina an escape from their nitpicking mother, and it gave her a place to belong after losing her close circle of friends in New York. But Maria's plan backfired and Tina and Robert fell in love with each other, and now no one is happy. Maria can't imagine leaving Robert, but keeping Robert and Tina apart makes them both miserable. Faced with an impending disaster, Maria comes up with a desperate plan to share her boyfriend with her sister.
The proposal is risky and could end in heartbreak for everyone. But with luck, a little love, and a lot of hot sex, Robert, Maria, and Tina might just make a crazy happy family of their own.