Suugaku Girl: Fermat no Saishuu Teiri

A math enthusiast meets a brilliant girl named Milka shortly after starting high school. Milka challenges him with math problems and shares elegant solutions, and they often discuss mathematics in the library. A year later, he meets Tetra, a younger girl who wants to learn math. As he teaches her, she slowly begins to appreciate the beauty of the subject. In the second volume of the series, topics such as Pythagoras Theorem, elementary number theory, groups, rings, fields, and Fermat's Last Theorem are explored.