Anata e Sasageru Sadistic

Shibasaki is a high school teacher widely admired by everyone at school for her deep love of her students and her gentle personality.
One day, she sees the truant girl Masono being bullied and steps in to help her. But when she visits Masono at home to learn more, the answers Masono gives are not what she expected.

(Source: Comic Gamma Plus, translated)