Genkei; Your twin brother, you are both 15 years old, you don't go to the same high school. Because he is more hard-working than you, he got into a high school with higher scores, and you go to a classical high school.

Even though you and Genkei have the same hobbies and are even very similar, you often fight and make fun of each other

While you were playing a computer game in your room, he suddenly entered your room and looked at you annoyingly, he smirks just to annoy you