INTERNATIONAL MANGA AWARD: The Quiet Don: Yakuza Side Story

Being the only son of the leader of the largest criminal organization (yakuza) in Kantō area, Shizuya Kondō chose not to join the gang and became a rookie designer of an underwear company. However, the assassination of his father forced him to inherit the gang, with one condition: keeping his day job while hiding his true identity from his coworkers, including an aspiring female designer, who is his love interest as well as the only person capable to keep his violent instincts contained.