homosexual supporting cast

A phrase used in the anime "Ouran Highschool Host Club" when one of the characters named Tamaki Suoh explained that since he and Haruhi are the main characters, they clearly must be love interests. His response to the twins' question when they asked him what the rest of the group was, he said they were the "homosexual supporting cast. In summary; he meant that he and Haruhi were straight while the rest of the host club was gay.