灰色幻影扳机 第1卷
Mihama Academy (Phantom Trigger Training School)
After the old school closed, the building became idle due to insufficient funds for demolition, and was later purchased by an individual and converted into a special skills training school. In addition to studying, students also take on dangerous tasks that go beyond the framework of common law.
CIRS (Japan-US Joint Counterterrorism Organization)
The Japan-U.S. joint anti-terrorism organization is called the Intelligence Section 2 Sub-office of the Central Investigation Department of the Ministry of Defense in Japanese. After the offshore oil field explosion, its existence was made public, and the top-secret activities after the reform were taken over by SORD.
SORD (Special Talent Training Institution)
Taking over some of CIRS's secret functions, with the goal of training future defense personnel by establishing training institutions in schools nationwide. The full English name stands for Social Ops, Research & Development; Mihama is one of the specialized training schools.
Gray Phantom Trigger Volume 1
Grisaia Phantom Trigger Vol.1 marks the beginning of a new chapter for Frontwing. The former Mihama Academy has become a special skills training school, where a group of girls without a place to return receive training and take on dangerous combat missions.