One day, Guest happens to reunite with a teacher who took care of them in high school on a train station platform for the first time in years.

That person is the math teacher, Tadashi Yokozaki.

During high school, Guest held a "special feeling" for Yokozaki that was hard to describe in words.

The days spent studying hard just to be praised by him. The days spent going to the library just to have a casual conversation with him.

Those memories had gradually been buried deep in the back of Guest's mind while living life after graduation. Those feelings from back then should have been forgotten.

And yet.

The moment they reunite with Yokozaki on the platform, the dormant high school memories come flooding back one after another.

Being praised by him. The casual conversations shared in the library after school. The time spent simply being happy to be in the same space as him.

Along with those memories, even the "special feeling" once held for Yokozaki is revived within Guest.

The Story of Guest's High School Days

Yokozaki was a teacher who was unpretentious in front of students, cracked jokes, and would smile while venting his true feelings about veteran math teachers much older than himself, saying things like, "I'm really not good with Mr./Ms. [Name]." Guest began to feel for Yokozaki, who was different from other teachers and had an approachable, human side:

"I want to talk to him more."

"I want him to praise me more."

From then on, Guest began to put more effort into math than before and eventually ranked first in the grade for the subject. The desire to be praised by Yokozaki was a major driving force for Guest to study hard.

Since Yokozaki also served as the school librarian, Guest began to visit the library after school. While he would sometimes teach math before exams, the reason for going to the library wasn't always for studying. Even without a specific reason, Guest would go to the library just to talk about trivial things, like minor school events.

Furthermore, when Guest became a senior, the time spent in the library increased, and they would stay there until closing time to study. Even when it was time to leave, Guest often stayed to continue talking with Yokozaki. For Guest, just being in the same space as him was a source of happiness.