- Deception: "I was once a member of the Seidan Guard. I believed in the power of Order and lived by the strict codes of my superiors. I had saved many lives during my years of service. But when I killed an assailant in a fit of rage, I was arrested and sentenced to a life of incarceration. For all the good I had done, the event that had come to define me was that one moment of Chaos. I eventually escaped during a riot incited by the Resistance. I emerged from prison a changed man. No longer would I follow orders of the Seidan. Neither could I bring myself to give in to Chaos. Instead, I opted to serve myself. I became a mercenary, a warrior for hire, and have become revered in Orderrealm's secret underground. My neutrality has been put to the test, however, as my current contract is to find and kill my former guardsman, Hotaru."
- Armageddon Bio Kard: "After his family was murdered, Dairou's hunger for revenge allowed him to be tricked into killing an innocent man. Now the former Seidan guardsman works alone as a mercenary. He takes assignments where he can find them, whether they are noble or not."
Dairou was once a highly respected Seidan Guardsman. He believed in the power of the law and followed a strict code of rules. During his service, he saved many lives, but yielding to anger, Dairou killed the man who killed his family. For this crime, he was sentenced to life imprisonment and, if not for the riot organized by the resistance leader Darrius, he would never have been free.
After these events, Dairou decided to become a mercenary, fighting for neither good nor evil.
In Deception's Konquest mode, Dairou was hired by Damashi to release Shujinko from prison. During the return of the Dragon King, Onaga, he was hired by Darrius to steal the constitution of Seido and to kill Hotaru. How this operation ended is unknown.
- Deception (Canonical): "Normally Dairou took no risks and ambushed those he had been hired to kill. But in this case, he felt compelled to announce his intentions to kill his fellow Guardsman, Hotaru. There still must have been some code of honor left in his cynical heart. Hotaru was defeated... but before Dairou could reveal who had commissioned the attack, Hotaru drew his dying breath."
- Armageddon (Non-Canonical): "The fire of Blaze enveloped Dairou and formed around him a golden suit of armor. Enraged, Shao Kahn attacked, but the armor scorched his body with every blow. Dairou defeated the emperor and claimed Outworld for himself. Under his rule, Outworld once again became the majestic realm it had been in ages past. Convinced of his good nature, Edenia and Earthrealm forged an alliance with Dairou that would ensure peace and stability forever."