Originally, Aichi Coexistence Private Academy was an all-girls school for privileged young ladies until it was decided that it would become co-ed. The fearful girls were permitted to bring weapons to protect themselves, and then a vigilante group was established called the “Supreme Five Swords." When rebellious Nomura Fudou is sent to the academy, he is given two options: act and dress like a girl or be expelled! 
 
(Source: Sentai Filmworks)

Bundled with the limited edition 7th volume of the Busou Shoujo Machiavellianism manga. 
 
Disappointed by how all members of the Supreme Five Swords were single-handedly taken out by the Empress, the headmistress ordered the Five Swords to a recreational trip to strengthen their bonds. Apparently, there are some extra budget to accommodate an extra sixth person on the trip. Both Rin and Mary wanted Nomura to be sixth person, but there may be some hurdles on making that a reality. 
 
(Source: Muse Asia)

The Private Aichi Symbiosis Academy was originally a high school for high-class girls, when it became co-ed, the girls, out of fear, asked to be permitted to bring weapons to school. When that was enforced, a five-member vigilante corps-like organization called the "Supreme Five Swords" was also formed.
After many generations, the five swords eventually became a group which corrected problematic students and such the academy started proactively accepting such students in order to correct them.
Nomura Fudou was sent to that school after being part of a huge brawl, what will he do when the only options he has after enrolling are being expelled from that school too or being corrected the way the rest of the male students there were… by being forced to dress and act like girls!
 
Note: Includes 3 extra chapters.

Tsunemi Touko