Even if it's against your moral code to take without returning, you should institute a liberal "boyfriend's closet borrowing policy" this fall. That way, you can go back to school in guy-inspired threads -- our favorites are the oversized long blazer (yes, boxy shoulders are back) and bomber jackets (which are too classic and cozy to ever really go out).
Girls, wear a blazer well by pairing the its structured lines and crisp lapels with contrasting styles, such as skinny jeans or leggings with mini dresses or lacey tops. Give it a "Gossip Girl" look by selecting a blazer with a private school vibe, incorporating details like piping, pins or crests.
Guys, you can wear a blazer or leather bomber jacket and make just about anything else look more stylish. But consider this your warning: As soon as the weather turns truly chilly, your best girl may try to permanently borrow your bomber jacket. That's because this tough piece will look Hollywood chic over a vintage maxi dress or her fave pair of faded jeans, and will remind her of you every time she wears it.