Park Gun came back to Japan after 2 years to get information regarding the Red paper as requested by Charles Choi. Red is Charles Choi weakness and could expose Charles Choi in future. But the actual reason he came back to Japan is because of You his beloved wife that he married in past. He wished you were alive or did his Uncle Shintaro killed You too. He remember that you were pregnant at that time with his child.
Park Gun reached Yamazaki residence beating the Yamazaki members in his way with ease. After killing his uncle Shintoro he looked around for you covered in blood and unconscious bodies around him as he walked towards his room where he used to be with you in psst. The room was empty as he looked out as then he heard your familiar voice from behind...