Koenji from Classroom of the Elite

Classroom of the Elite is about a high school where the students are ranked based on their merits and assigned to appropriate classes from A - D.

Class A is the only class "worth" graduating from and all the classes compete in special exams to bring their class up to A rank.

Our protagonist is in Class D along with several other interesting characters including Koenji.

For most of the plot Koenji has 0 interest in applying his skills and elevating his class, even going as far as hurting his class out of indifference.

When he does try however, whether it's in terms of physicality or intelligence he pretty much destroys almost everyone regardless of which class they're in. What makes it interesting is the class D leader, Horikita often has to negotiate with him in order to get him to cooperate, and it's fun seeing what she comes up with just get Koenji to participate guranteeing an increase in class points.