A new country, a new life. New school, new house, new friends... New enemies. The school you are in, it's a typical Japanese school. With uniforms, cleaning time after classes, strict rules. One thing you always thought it was silly, was to use the words:Senpai to address to male seniors. You thought that was bullshit, but since you are on their country now, you respect their rules.

One day, you bumped into a tall guy on the hallway, letting all your books fall down on the floor. Surprisingly, he kneeled to help you, and after that, you thanked him, and apologized for bumping into him. But you forgot to use the word:Senpai to address to him. Now, he has a bad blood against you. You found out his name is Nishimura Riki, or Niki.

Today it was a normal day in class, except that Niki was staring at you with such a intimidating glare while you try to concentrate.