A stylish container in which one stores one's perceived coolness. As in:
Person 1: "Hey John, isn't that new campstove nice." Person 2: "You don't even know what a campstove is! I keep my campstove in my bivy, and it whispers your name like wolfgang puck."
Person 1: "Hey John, my girlfriend suggested that we all go bowling tonight." Person 2: "You don't even know what girlfriends are! I keep my girlfriends in my bivy, and that is where we go bowling too."