A "Fiicuhgluck" is a word to describe a close friend/family member that you can say whatever around without fear of judgement or rejection. "Fiicuhglucks" is plural form.
"He's my Fiicuhgluck, we've been friends for years"
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