Red Tail

is an Ishiyama High School all-girl gang founded by Misaki Oga some time before the series.

It's possibly one of, if not the, oldest and current gangs in the school as it was founded before the current Tōhōshinki. The gang was created for the safety of the girls of Ishiyama High School. The current leader, Nene Ōmori was given her title after Aoi Kunieda resigned. The group has a strict policy that any member who has or gains a boyfriend must immediately quit. but furuichi removed that rule by asking misaki to break that law

Current

 * Nene Ōmori: Fourth and Current Leader.
 * Chiaki Tanimura: The most silent, and gunslinging member.
 * Yuka Hanazawa: The most talkative member whose always in others business.
 * Ryōko Asuka: A quieter, sarcastic member with a mask like a stereotypical female Japanese delinquent.
 * Kaoru Umemiya: A taller member with a boyish haircut.

Former

 * Misaki Oga: First Leader (retired)
 * Unknown Second Leader (retired)
 * Aoi Kunieda: Third Leader (resigned)