A scheming (but refined) top finishes teaching senior high school and is unexpectedly reassigned to the first grade as a homeroom and math teacher, covering for a colleague on bed rest.

As a math Olympiad prodigy, he quickly raises the class’s overall performance—except for one particular little rascal.

After reviewing the kid’s hopeless test and homework sheets, the teacher calls the parent:

“Do you never help your child with their homework?”

The clueless bottom feels his world collapse:

“I help him every single day!”

Still so many mistakes?

Teacher: … “Come to school when you have time. We need to talk.”

⸻

The bottom, trembling like his son, is terrified of being summoned by the strict homeroom teacher.

But when he arrives—he blacks out for a moment.

That teacher… is the very same man from a passionate spring night seven years ago.

He has no choice but to take his son’s homework more seriously.

And yet… the very next day, he’s called in again.

The top shrugs: “How about this? I’ll tutor you. You go tutor your son.”

Each visit, the tea gets more refined.

The bottom, of course, is oblivious.

Bottom: “Kid, can’t you pass just once?”

Son: “Math is too hard, Dad…”

He comforts himself—there’s no way the top would ever guess their secret. That must mean he’s smarter.

…Until one day, overwhelmed with doubt and thinking he must have mistaken the man’s identity, he secretly swabs some of the top’s hair for a DNA test.

Just as the results come out—

The top sees it.

Bottom: O_o

Top: 🙂