Kiyomi Takada first appears as Light Yagami's classmate and brief romantic interest at To-Oh University, earning the title "Miss To-Oh" or "Refined Takada" due to her popularity and dignified demeanor. She later resurfaces as an NHN news announcer, personally chosen by Teru Mikami to serve as Kira's public spokesperson, delivering Kira's messages to the world with calm authority. Recognizing their past connection, Light initiates meetings under the guise of aiding the Kira investigation, secretly establishing her as an intermediary between himself and Mikami.
During a monitored meeting, Light engineers a scenario to have surveillance removed, reveals his identity as Kira, and recruits Takada as his ally in creating a new world order. She embraces the role, motivated by admiration for Light and rivalry with Misa Amane, whom she openly dismisses as unintelligent during a confrontation. Her duties expand to relaying Light's instructions to Mikami, including directing him to provide her with Death Note pages for killings while he maintains a decoy notebook.
In *Death Note Relight 2: L's Successors*, the absence of the mafia storyline accelerates events, leading Takada and Mikami to collaborate directly under Light's orders much earlier. They eliminate members of Near's SPK organization after Light obtains classified information on their identities. This OVA also portrays Mikami killing dissenters during a televised debate, an action outside the primary continuity; Takada's direct involvement in this specific act is not detailed.
After Mello kidnaps her, Takada uses a hidden Death Note fragment to kill him. Light then forces her to commit suicide by writing her name in his Death Note fragment to eliminate her as a liability. Unbeknownst to Light, Mikami simultaneously writes her name in the genuine Death Note minutes later. This duplication exposes Mikami's actions to Near's team, directly contributing to Light's downfall. A post-credits scene in the OVA shows the task force discovering Light's body.
In the live-action film *Death Note: The Last Name*, her character replaces the manga's Kyosuke Higuchi. Rem provides her with the Death Note, leading her to kill a professional rival to advance her career while also eliminating criminals under Light's direction. She is later killed by Light to regain ownership of the Death Note after her arrest.