Shuu is an exceptional marksman who earns a living by eliminating highwaymen (bandits) alongside his companion Alice, a celluloid figure. When asked about his motives for killing them, he labels them as "scoundrels." Although Shuu possesses remarkable accuracy with various firearms at long range, he is unable to engage in close-quarter combat due to psychological distress. He devotes most of his time safeguarding the remnants of a deserted metropolis.