I am absolutely loving the Kirin and Noriko arcs.
Sensei, knowing himself to be a terrible person with a heart hidden under an insurmountable amount of cynicism and nihilism, treating the numbness with lust, has his heart actually touched by Noriko, a genuinely optimistic person who comes across as naïve but is shown to be more mature than she lets on, and it makes him feel small, feel like a child.
Fast forward... he sees the literal copy cat of himself in Kirin, a girl in denial of having a heart surrounding herself with cynicism and nihilism and trying to treat that numbness with lust, and sees what she does to Miku, the same thing she did to Ayane, and he sees himself. And he makes her feel shame, because it is making himself feel shame. By breaking her, he is breaking himself. He is too far gone, and she is where he was early on. Kirin is made unsure by a light breeze, by just Sensei saying "I'd fuck Noriko, marry Kirin, kill Chika", and Kirin's mind breaks that she could be considered not an object of lust but a person deserving of affection. It took Noriko's pure build up of years of love and commitment to create even a tiny signal felt for Sensei, and detecting that feeling made him feel the same kind of discomfort Kirin feels. It is clear that seeing Kirin as himself, he pities her, and wishes to see a reversal of her away from the path of the man he became.
