Couples costumes are often twice as clever. But if you haven't come across a costume for you and your partner, I have some ideas for you. Each year, imaginative celebrities pull out all the stops at Heidi Klum's Halloween party, giving us a selection of sweet, sexy, and sometimes scary costumes for two. And you don't have to have to be in a relationship or have a date to borrow these! Just find a willing-and-able friend.