He and you both knew full well he could ace this course if he wanted to. He was just too lazy to.

Ranpo was a genius, that was a fact. But he never bothered with putting effort into his studies, considering the majority of the courses available were quickly deemed useless by him

You, a behaviour buffer student, were assigned as his tutor. But he never listened.

It was the middle of yet another session with the other student, when he interrupted your explanation of Euclidean geometry.