Tanimura's sub-stories often involve his detective work, helping citizens with various problems, or dealing with the criminal underworld in his own unique way. Many of these quests involve investigations, interrogations, and using his arrest techniques. 'The Stolen Bag' is a classic example, where Tanimura must track down a thief and recover a stolen item, often leading to a combat encounter where arresting the culprit is key.
A significant sub-story for Tanimura is 'The Art of Evasion', which introduces him to Master Nair, who teaches him advanced parry and evasion techniques, further enhancing his defensive combat style. Other quests might involve helping foreign residents, dealing with corrupt officials, or even participating in a bizarre 'hostess club' investigation. His sub-stories are excellent for earning extra money through arrests and honing his unique combat skills.