突然の父の死に動揺する涼に、芭月家の家事手伝い・稲さんは一通の手紙を差し出す。父宛であるその手紙は、朱元達という差出人のほかは全く読めない文字で綴られていた。涼は自分の知らない父の情報を求めて手紙を調査するが、そのうちに横須賀港を裏で仕切る『マッドエンジェルス』のチャーリーに目をつけられてしまう。

Hazuki Family's maid Ine hands a letter to Ryo, who is restless from his Father's death. The letter was sent from a person named "Yuanda Zhu"to his father which contained characters he cannot read. Ryo begins investigating the letter to find out his Father's past. As he further investigates, he is targeted by "Mad Angels", the gang that runs Yokosuka Harbor's underground business.