Taro Sakamoto was once a legendary hit man considered the greatest of all time. Bad guys feared him! Assassins revered him! But then one day he quit, got married, and had a baby. He's now living the quiet life as the owner of a neighborhood store, but how long can Sakamoto enjoy his days of retirement before his past catches up to him?!

Sakamoto comes running to Shin's aid and clashes violently with Shinaya, who's being controlled by Gaku! Our heroes are striving to get information on X, who continues to operate in the shadows, but nothing has gone as planned during the JCC transfer test. How will it all end?!