Loser is prologue to the tenth Durarara!! light novel.
Hiroto Shijima despairs over his loss to Izaya Orihara at the Amphisbaena parlor a few days prior. He retreats to his home, intending to seek help from his family and use their influence and power to achieve his revenge. When he does, he sees a guest had arrived and was having a discussion with his father and grandfather. He is introduced to Jinnai Yodogiri and his secretary Kasane Kujiragi. Hiroto's grandfather Giichiro reassures Hiroto that he'll take care of Awakusu-Kai but in exchange he must follow Jinnai's instructions.
Jinnai (to Hiroto): "Izaya Orihara thinks he's got you completely within his grasp. You've worked your way in extremely close to a number of 'things' I seek. And now you and I are connected. It's a wonderful orchestration of fate, don't you think?"