Lauren says "Ohh Ashleigh, where's your bag strap? all I can see is your boobs.."
Ashleigh replies "Can't you see it's stuck in my cleavage..."
Lauren" Haaaaaa you've got a Boob Bag!!"
When wearing a shoulder-strap bookbag or laptop case, and you have slight to extreme man boobs, it accentuates these man-boobs causing a feeling that everyone is staring at your fatness.
Person 1: Dude, watch out on that strap.
Person 2: Why?
Person 1: You're developing bag-boob
Person 2: Damn. Everyone can see my man boobs?
Person 1: Yup.