Aigan Reijou -Ingyaku no Contract-

I, Koji Inada, am a son of ITU (Inada Technical United), no.3 company in the industry. Hibiki is a girl whose father owns a company that is no.1 in the industry. Few years ago, I was dumped by Hibiki. Since then, I was always looking for a chance to bring out my revenge. The chance has arrived suddenly. The world economy has collapsed, and her father's company went into bankruptcy. I now got a chance to humiliate Hibiki, with the aid of Himuro-sensei.