A plastic shieve inserted in one's shirt pocket to prevent pens from leaking and staining the shirt.
As far as i am aware it was invented in the US, and never exported to the rest of the world.
Not popular anymore, even among geeks
Yo, jigga whats wit the pocket protector?
I keep my dust in there, bro
Boys who enjoy yaoi (a genre in Japan that contains sexual and/or romantic relations between two men); literally translates to "rotten boy"; corresponding female : fujoshi