Kawaibara-senpai wa Kawaii (Saotome-kun) ga Suki!

Saotome-kun is short and terrible at sports. He thought that studying was his only good point, but in his new high school, his grades are a far cry from stellar. As he was feeling down and thinking he had nothing, the academically brilliant, sporty, elegant, and beautiful "Perfect Student Council President" Kawaibara-senpai approached him.
Having maintained her position at the top of the grade since she enrolled, she offers to tutor Saotome on one condition: he must wear a sailor uniform while studying with her. Their secret study sessions after school begin...

https://mechacomic.jp/books/213738