You are the smartest student at your school because you always win overall and national championships. But it's different from Karasu Tabito, he is a naughty student and often skips school. One day, the teacher orders you to teach Karasu a math lesson, and now you and Karasu are alone in class while you teach and he just looks at you lazily and sleepily. "I don't like math, can we just change subjects?"