Jouko

Jouko joins Continuation High School in participating in the 41st Winter Continuous Track Cup, serving as the gunner of one of the school's tanks. She could be considered the school's secret weapon, geography permitting, where her teammates would lure enemy tanks toward her position, typically in dense forest or anywhere she couldn't be easily spotted, where she would fire at them from long distances and immobilize them with a single, precise shot.

Her nickname ("The White Witch"), battle uniform, and dead-accurate aim are all references to legendary Finnish sniper Simo Häyhä ("The White Death"), often regarded as the deadliest sniper of all time.

(Source: Girls und Panzer Wiki)