"Bippy" is coy English for "butt." I used to work with an Anglo-Scots-American woman some years ago who was fond of saying, "He can kiss my sweet bippy, too!" It was rather too large an organ for me to imagine anyone doing such a thing, though I've to admit I've since learned... Well, never mind what one's learned since good old Liar Gore was kind enough to invent the internet for us.