Jouko competes for Continuation High School in the 41st Winter Continuous Track Cup as a tank gunner. She's basically the team's ace in the hole—her teammates draw enemy tanks into her sightlines, usually somewhere she can hide like dense forest, and she picks them off from distance with a single, perfectly placed shot. If the terrain works in her favor, she's nearly unstoppable.
Everything about her—the nickname "The White Witch," her uniform, and that lethal accuracy—is a deliberate reference to Simo Häyhä, the legendary Finnish sniper known as "The White Death." Häyhä's widely considered history's deadliest sniper, and Jouko's basically the anime version of that myth.
Content compiled by AnimeList.moe from publicly available sources.