Kei Yuuki is a prominent crew member aboard the Arcadia in the anime series 'Uchuu Kaizoku Captain Harlock' (Space Pirate Captain Harlock). Serving as the ship's communications officer, Kei is known for her calm demeanor, intelligence, and unwavering loyalty to Captain Harlock. Her strong sense of justice and empathy make her a trusted confidant among the crew. Throughout the series, Kei plays a vital role in relaying information and supporting Harlock’s fight against the oppressive Mazone, contributing significantly to the Arcadia’s success.