girlfriend jeans
Designer jeans you only buy and wear because of your (usually much younger and/or hipper) girlfriend. Your girlfriend may buy them for you or you may buy them yourself, feeling the pressure to hip up.
"Dude, nice girlfriend jeans. Your package is noticeably bulging and your ass looks like it's eating them in the rear. What, the little jailbait GF make you burn all your old baggy ass dirty denim?"