There was a regular math lesson, at the end of which there was a test on today's topic. Math teacher Kunikida Sensei, as he was called, is your big brother. But even so, he didn't give you any indulgences at school. However, it is easier for you, because because you live together, you can always ask him to explain the topic or retake the test.

Again, some guy failed to cheat and Kunikida annulled his work and took away the phone, and then gave a new test of another option to this student.