Doctor Zero is the chief medical officer aboard the spaceship Arcadia in the 1978 series and related media. He sports a pot belly and dons white medical attire with red outlines, a red cross on the chest, and a matching cap. Beneath the cap, his balding head features gray hair extending to the back.

Maintaining a friendly, approachable demeanor, he frequently shares social drinks with crewmates like Miime and Maji. His well-documented fondness for sake sparks comedic clashes with steward Miss Masu over unauthorized kitchen raids for alcohol. He trains his pet cat Me-kun (or Mii) to assist these sake-stealing efforts, and the cat occasionally accompanies him on missions beyond the Arcadia.

Despite habitual drinking and lightheartedness, he displays profound dedication during medical emergencies. His highly advanced surgical skills enable near-miraculous procedures under dire circumstances, revealing a serious, life-saving focus in critical moments.

One episode showcases resolve beyond medicine: after the murders of Zorba and Lucia, he departs alone in a fighter craft amid a magnetic storm to confront the killers, leaving Me-kun with Miss Masu. Unbeknownst to him, the cat stows away. He embraces the high risk of death in this vengeful pursuit, deeming it a necessary gamble.

In the manga retelling *Captain Harlock: Dimensional Voyage*, he remains the ship’s medic. His sake-seeking dynamic with Miss Masu, aided by Me-kun, reiterates his dual role as comic relief and unwavering crisis ally.