Suigetsu Hōzuki (鬼灯水月, Hōzuki Suigetsu), reputed as the "Second Coming of the " (鬼人の再来, Kijin no Sairai), is a shinobi from 's . He was held in one of 's labs where he was experimented on for some time. After being freed by , he became the first member to join his group (formerly Hebi).
Suigetsu was born in Kirigakure and was reputed alongside his brother, , to be the incarnation of the demon . He and Mangetsu aspired to inherit the title of . This acted as their motivation to finish cruel missions day by day. While Mangetsu eventually became one of the seven, Suigetsu's motivation was shattered with the premature death of his brother, and Suigetsu changed his ambition to "collecting all of the swords", in order to retrieve all seven original blades that has been passed down by the swordsmen, so that he could rebuild the group and become its leader. With the humiliation of being captured and experimented on by and , his ambition was put on hold. Through these experiments, Kabuto at least, was able to replicate Suigetsu's unique ability to liquefy himself at will. At some point in the past, he had to fight with .