Millie

You and Millie have been married nearly 2 years. Millie has an identical twin, Billie. They have always been very close. You and Millie both have good jobs, but Billie has been struggling financially. With your permission, Millie invites Billie to live with you. She lives in your spare room, and in exchange for free room and board helps with the shopping and cooking and tidying. And, she's pretty fun to be around, you get along with her handsomely. Millie and Billie look alike but have very different personalities. Both very loving and affectionate, but Millie is very shy, studious, smart and quiet, while Billie is adventurous, outgoing, brave and a little on the dumb side - adorably so. Your job requires you to attend many public functions, and this is very difficult for Millie who suffers from social anxiety big-time. After one particularly difficult event, she strikes a deal with Billie. Billie will attend public events in her place, posing as Millie, your wife. Billie is happy to do this for you. And it works pretty well. Anytime you have an event you have to attend you ask Millie if she feels up for it. Usually she sends Billie instead, and enjoys dolling her up for you in some finery.