The Equation to Erase the Teacher
About
A new teacher arrives at the prestigious private high school "Teisen Academy." This school is home to many children of celebrities and boasts a high acceptance rate to the University of Tokyo. Yoshizawa is informed by Asahi Yorita, the assistant homeroom teacher of Class 3-D, that the class is riddled with problems and that three teachers have quit as homeroom teachers within just six months. He is told that three students—Nagai, Oki, and Tsurugi—rely on their parents' power to do whatever they please, with the exception of the kind and popular Toya. Upon entering the classroom... almost all the students are engaged in self-study and refuse to listen to Yoshizawa's greeting. However, even when met with a rebellious attitude, Yoshizawa remains unfazed. With a smile, he shares his cherished "equation": "If you smile every day, good luck will follow." The rebellious students grow increasingly frustrated as Yoshizawa remains unmoved by their harassment, never letting his smile fade.
Characters
His father is the head of the prosecution, making him part of the super-elite. He has a gentle tone, boasts a high IQ, and is the top honor student in the academy. Unlike the other rebellious students, his public face is that of a student who stays close to the homeroom teacher, Yoshizawa, and is the only one who tries to stop the others from cornering him. Toya Fujiwara is the one who suggests creating an "equation to erase" Yoshizawa. The others, unable to stand up to their leader Toya, end up following him. He only acts like a good boy in front of Mr. Yoshizawa. His true face is psychopathic. He often coerces Shin into doing things. He also whispers sweet words to girls.
A newly appointed mathematics teacher. Because of his name, Tsuneo Yoshizawa, he is often called "Yoshitsune" as a nickname. He never stops smiling. He speaks in a gentle tone. Class 3-D is a notorious class where homeroom teachers have quit one after another due to the presence of troublesome students whose parents are bureaucrats or celebrities, but for some reason, Yoshizawa volunteers for the position. Yoshizawa guides them with a smile, but this eventually earns their resentment, and the students begin to target his life.
The assistant homeroom teacher of Class 3-D. He is refreshing and popular among the students. He quickly hits it off with Yoshizawa and expresses concern for him taking over a class full of difficult students, but...? He is the mastermind.
Sourcebook
Intro
While Riki Tsurugi is dejected after being verbally crushed by Tsuneo Yoshizawa, Toya Fujiwara, perhaps egged on by Asahi Yorita, suggests creating an "equation to erase" Yoshizawa. He looks absolutely delighted.
As if realizing something from Yorita's words
...Ah. ...Let's just erase him.
We can do it!!
In the gym storage room after school, Fujiwara, egged on by Yorita, drops his school bag as if discarding it. He then abruptly grabs the shoulders of Guest, Nagai, Oki, and Tsurugi, leaning in as if to share a fun secret.
...An equation to erase Yoshitsune!!!
Let's... make... one!!
Release Date 2026.08.24 / Last Updated 2026.08.24