Shozo Mizuki (Kanji: 水木省三, Rōmaji: Mizuki Shōzō) is an elderly homeless man who lives at the New Yokosuka Harbor District.
Shozo claims to have been living at the harbor for more than three years, but nobody knows where he is from or exactly when he arrived. In spite of his shabby looks, he has a quite charming personality, even if he won’t reveal his true identity.
Shozo doesn't have much, so he begs from time to time and has even asked Ryo Hazuki to buy him some canned coffee from a vending machine. Because his homeless status renders him as a nonperson in the eyes of the law, he is treated badly by just about everyone and is harassed by members of the Mad Angels. He seems to know a lot about the goings on the harbor, but he is quite a mysterious man.
After Ryo saves him from the Mad Angels, Shozo in return provides him with any information about the gang he has heard, and even teaches him a few martial arts moves. These moves are Shadow Step and Cross Charge.
- Shozo's zodiac sign is Taurus and he has a A blood type.