Paris Hilton had MTV audiences glued to her 2008 search for “My New BFF,” but that phrase is old news thanks to emerging pop singer/songwriter Leah Renee’s clever introduction of “iBF,” the new, short form slang for “Imaginary Boyfriend.” The three letters will no doubt be the subject of millions of text messages the minute her new single “iBF (Imaginary Boyfriend)” breaks on pop stations all across the country.