蒼井 碧

A reserve student and shooter in Mihama Academy's CIRS division, also known as the "Phantom Triggers" back in the day. An upper-type assassin from Hollow House, Aoi was given to her master, Sengoku Ichiru, as a gift when she left her family home. As she graduated from Hollow before the regulations were tightened, her generation is seen as one of the most dangerous - maybe it would be more accurate to call her a tool of "national offense," rather than "national defense." She often tried to resist her "brainwashing" by disobeying her master's orders, which tended to cause her great agony. Her full name may seem like a joke, but Aoi liked it because it was easy to remember. She ended up looking after baby Haruto whenever Ichiru entrusted him to her. "Ya heard the man. Sorry, but I ain't got no time to beat ya to death at leisure." [From official English site]