Not much is known of Kiko's background. She is first introduced in Nightfire's second mission, The Exchange, seen waiting in the parlour looking out of the window. If approached she will say "I'm waiting for someone", referring to Alexander Mayhew. This is the only time in the story where the player can come this close to Kiko.
After Defeating Drake's Henchman, Bond Proceeds to spy on the secret meeting in which Alexander Mayhew, Phoenix International's chief officer in Japan, provides Rafael Drake with a stolen missile guidance module. At this moment CIA agent, Zoe Nightshade, is caught and taken to the conference room. Drake is furious and threatens Mayhew with death if the Security Breach leads back to Japan.
Kiko is later seen giving Mayhew a massage when Bond arrives at his Japanese estate. After Bond demands the data files containing information on Drake's high-tech operation (codenamed Nightfire) Kiko receives a pager alert indicating that there are intruders on the premises. She then draws her gun and leaves. It is hinted that she leaves in order to allow Drake's men in for the purpose of killing Mayhew. She suddenly reappears after Mayhew is killed by a ninja assassin. After expressing her sorrow, she and Bond leave for the Phoenix Building in Tokyo to retrieve the data files.
Arriving in downtown Tokyo, Kiko informs James that the building would be heavily guarded and advises him on where he may find the files. Bond then infiltrates the building, makes his way to the mainframe room and locates the files. Kiko is then briefly heard to be involved in a scuffle with Drake's security forces, after claiming that they were waiting in ambush for Bond on the ground floor. After some sounds of a struggle, Kiko's line to Bond goes dead. Bond makes his way towards the helipad where he meets undercover operative Dominique Paradis. She informs him that the files were bait for a trap, although both are unaware that it was Kiko who orchestrated it. 007 then escapes the tower by parachuting from the rooftop.
Kiko is next seen waiting for Bond at the nuclear power plant he has been investigating. She helps him aboard the waiting helicopter and they fly off. While resting aboard the aircraft she approaches him and shoots him with a tranquilizer dart.
- "You must be tired James. What would you say to a little Nap?"
- ― Makiko Hayashi.
Arriving back at the Phoenix Building, Kiko and two thugs escort Bond to Drake, who is dining with Dominique on the top floor of the building. After announcing that he is aware of Dominique's betrayal, Kiko is ordered to throw her over the side of the building. Dominique attempts to defend herself and after providing a distraction for Bond's escape is kicked off the helipad by Kiko. She falls seventy floors to her death in the lobby below.
Final appearance and death
Kiko is next seen in the mission Countdown, where she seems to be the head of security for Drake's launch site. She announces to the guards that she fears Bond has penetrated their security and orders all sectors to be locked down and all codes other than hers cut off. Bond is then tasked to follow her through different corridors to the control center (guided by Australian intelligence agent Alura McCall).
She is not seen again until 007 makes his way in to the shuttle launch silo. Kiko sneaks up behind him as he enters, flicking a switch to release the landing platform - causing bond to fall into the launch silo. Taunting Bond from behind the shatter-proof glass partition of an elevator, she sends her minions to kill him. After a skirmish, he emerges triumphant and Kiko attempts to flee to a shuttle. Bond, however, gives her a taste of her own medicine and drops the launch platform causing her to fall into the blast chamber is trapped and incinerated by rocket engine flames.
Kiko appears as a playable character in the Multiplayer mode in Nightfire. She only has one skin (the leather suit).