"Pop-Pop" is a nickname for George Bluth primarily used by George Michael and Maeby Fünke. It is mistakenly interpreted by Michael when George Michael remarked that he 'has Pop-Pop in the attic' - Michael thinks George Michael is implying he has sex (with Ann Veal) there. Later, both George Michael and Rita Leeds actually do use "pop-pop" to refer to sex. ("Good Grief")