Born in the village of Littner, Yoko was forced to go to the surface to fight the Beastmen and their Gunmen (mechs) in order to protect the village. One day, a Gunmen fell inside the underground village of Jeeha. Yoko followed it and met two young men in the village, Simon and Kamina. After defeating the Gunmen with help from Simon's Lagann, the three left the underground in order to defeat the Spiral King and stop the Gunmen menace.
Skilled Sharpshooter: Due to her constant practice, she's become the most skilled sharpshooter in the surface, being able to hit the most difficult of targets.
Skilled Pilot: She has been shown to be able to pilot all sorts of mechs, from regular Gunmen, to Gurren Lagann.
Spiral Power: Spiral Power is the energy that allows living beings to evolve and improve themselves. Like every human in the Gurren Lagann universe, Yoko uses her Spiral Power to power and pilot a Gunman. As Yoko's will to evolve and win gets bigger, her Spiral Power gets stronger, making her Gunman stronger as well.
Rifle: Her main weapon is a large rifle with two different ammunition types. The most common one consists of Uranium bullets, which can be used to pierce the exoskeleton of Gunmen. The other type of ammunition is only used for hunting, and it consists of Arrows, working similarly to a crossbow.
Handgun: She has been seen carrying a small handgun from time to time, and she's quite skilled with it as well.
Yoko M Tank: Yoko's personal Gunman. It resembles a walking head with arms, legs, and a gun barrel mounted on the top, which is its main weapon. During the Anti-Spiral War, it was equipped with Spiral Power barriers to effectively fight the Anti-Spirals.