Gunslinger Girl: Il Teatrino

 The Gunslinger Girl: Il Teatrino.

  When the Social Welfare Agency investigates the disappearance of an operative, their inquiry leads them right into the lair of their rival, the Five Republics. The assassin Triela infiltrates the hostile organization, but her search is cut short when she finds herself staring down the barrel of a gun... (Source: ANN)