Tight-rope (2012)

Naoki Satoya has been Ryuunosuke "Ryu" Oohara's best friend and closest confidant ever since they were young, even though most of their peers fear Ryu's family, the powerful Oohara yakuza clan. Now, mere months before Ryu is set to inherit his father's position, he declares that he instead wants to be a train conductor and live a quiet life with Naoki. Unwilling to let their legacy fizzle out, the Oohara clan enlists Naoki to persuade Ryu to change his mind. But when Ryu is resistant even to the words of his favorite person, Naoki wonders if there is a deeper reason behind Ryu's refusal. [Written by MAL Rewrite]