Tamoko was under five feet (one and a half meters) tall, with smooth skin and physical strength.
Tamoko was a native of Kozakura. She could not read Common and had trouble with the Kozakuran language. She was born in 1350 DR in the Kozakuran isle of Mikedono. Her father sold her to the ninja Konishi clan.
Tamoko was trained in the secret Konishi dojo in Chimotoge, becoming a ninja of renown. However, one day she was sent to kill a high ranking wu jen, but the wu jen was prepared for her arrival and managed to push Tamoko througg a portal to Athkatla in Amn. In fear both of the powerful wu jen and of the Konishi ninja for failing her mission, Tamoko remained in Faerun and started working as an assassin until, in Baldur's Gate, she met Saverok.
- In Baldur's Gate, Tamoko is first seen with Sarevok at the beginning of the game, when the protagonist and Gorion are ambushed by them and two ogres. In the cutscene, Tamoko curiously casts a Flame Arrow that does minimal damage to the protagonist, prompting Gorion to tell them to flee while he kills the ogres and incapacitates Tamoko with a Sleep spell.
- The next time Tamoko is seen is near the end of the game, when she approaches the player’s party with information about how to find evidence of the criminal acts of the soon to be grand duke Sarevok. She explains that she wants the player character to defeat him but leave him alive in hopes that, stripped of his divine ambitions, he may again become the mere man Sarevok whom she loves. She believes it is his tainted blood that has ruined him.
- The last time Tamoko is seen in the first game is when the player is approaching the temple of Bhaal that is the site of the final encounter in the game. Sarevok, angered at her betrayal, has sent her to die at the hands of the approaching player character, and she is determined to do so. By steadily refusing to kill her just because she is in their way, the player can show her they are different from Sarevok and thus convince her that his own attitude is more a matter of personal choice than she had realized. In this case, she will simply leave without a fight.
- In Baldur's Gate II: Throne of Bhaal, a different version of Tamoko is seen briefly when the player character has to face an evil version of themselves in the second test in the Pocket Plane. This evil version also has a party that includes a Tamoko that wields what appear to be a katana and a wakizashi. Sarevok’s ending story also mentions that he went to Kara-Tur to bury the body of Tamoko, who was his true love.