Grisaia: Phantom Trigger 5.5
Three months have passed since Arisaka Shiori started working at Mihama Academy.
She did her best to adapt to her unusual position as a teacher at the 'school of assassins' and somehow managed to gain the trust of her students. However, However, Haruto's evaluation of her was rather pragmatic.
"She's, uh, unusually modest, and a bit clumsy. But she's sincere, and she tries her best at everything she does... I think she makes a great teacher, but that alone isn't going to keep her at Mihama."
Arisaka, who was summoned by the principal based on her initial terms of employment, is asked whether or not she intends on continuing to teach.
"Let's get down to business - do you want to keep your job?"
"Can I ask you a question too? Am I... needed at this school?"
Arisaka begins to talk about her horrific past.
It's almost time for her to make her decision...

Grisaia: Phantom Trigger 06
It's the day that comes around once a year—a day when Haruto and the other members of a previous generation of Phantom Triggers make their way to a mountain summit. Atop that mountain lies Haruto's master—Aoi.
On the way, they reminisce about the life of Aoi, a young woman so vicious, and yet so pure.
As they do so, the secrets behind the reborn Mihama Academy begin to spill forth.
"All matter eventually breaks down, and every living thing eventually dies. Entropy. That's all there is to it."
Just what events led to Aoi's final moments in this world...?

Grisaia: Phantom Trigger 07
As daily life goes unchanged, the girls continue to sharpen their fangs in silence for the inevitable showdown.
Meanwhile, Shiori Arisaka finds herself in two minds. Should she allow her students to jump headfirst into this battle, or should she forbid it? Their fate lies entirely in her hands.
Harrowingly, at the core of the enemy forces are former Phantom Trigger members; Enishi and Kuroe. The climactic final confrontation is close at hand.

Grisaia: Phantom Trigger 08
As the battle with the enemy organization, The Fatal Answer enters its final stage, CIRS and SORD send their full forces into their adversary's stronghold.
Awaiting Haruto there are Enishi and Kuroe, former members of the Phantom Trigger. They clash with weapons and convictions, both sides knowing there will be no justice for the other. But when the furious fight comes to an end, what is it the girls see...?