From The TimeSplitters Wiki

Sadako
Unlocked by	Complete NeoTokyo on Normal
Species	Human
Size	Normal
Accuracy	6
Agility	6
Stamina	5
Fire Proof	n/a
Shock Proof	n/a
Default AI	3
Native TimeZone	2019
First Appearance	TS2 Story Mode
Relations	n/a
Games	TS2

Sadako is the leader of the hacker gang in NeoTokyo that includes Krayola, Barby Gimp and Milkbaby. The gang's hideout is located in the sewers of the city.

TS1 Gesture	N/A	TSFP Gesture	N/A
TS2 Gallery	Horrifically burnt in a tenement blaze when she was ten, Sadako's outer scars are nothing compared to the rage and hatred she harbors within. A self-taught hacker, she and her gang have stumbled across technology that could change the course of history...	TSFP Gallery	N/A

2019 NeoTokyo

Sadako's gang stumble across a TimeSplitter and place it into a stolen prototype of a Cyber Rig, to study it further.
She seeks vengence on Ghost, who refused to join her gang, and frames him for the theft of the Cyber Rig, causing him to be wanted by the Riot Police. She appears as the ending boss of the NeoTokyo level and when you fight her, turns invisible, making the job very hard. Funnily enough, her hat can be knocked off, to reveal a horrible scalp. Another interesting fact about Sadako is that she has no health bar like normal bosses in Normal or Easy mode; it only appears in Hard mode.