Sumaru

is a Genin from Hoshigakure. He dreams of one day becoming the Hoshikage.

Background
Like the other ninja of Hoshigakure, Sumaru takes part in star training, a technique which allow incredible chakra control, at the expense of severe physical health damage. He appears to be one of their more prodigious practitioners, being able to perform some of the more advanced techniques of star training at such an early age. Sumaru is told that his parents, Natsuhi and Hotarubi, were killed in battle guarding the fallen star, when in reality, they stole it in an effort to save the villagers from the damaging effects of star training. As a last favor, they asked the Third Hoshikage to lie to Sumaru to protect their family name.

Sumaru remembers his mother, especially, through a lullaby she sang to him as a child about a red star called Natsuhiboshi, which is actually the planet Mars. The lullaby serves as his motivation through a large portion of the story arc.

Plot overview
He first encounters Naruto at the edge of the Land of Bears where he stops the Konoha Genin from walking into a canyon filled with toxic gas, the "Devil's Ravine". Naruto misinterprets Sumaru's actions as an attack, and has a brief, uneventful battle, during which, the Leaf Genin witnessed first-hand the Mysterious Peacock Method in battle. When the star is stolen by a mysterious bandit, Akahoshi charges Sumaru and his friends to get it back. Sumaru is taken away by Akahoshi posing as the real mysterious bandit as the other ninja collapse from the side effects of the Star Training.

Akahoshi puts him in "suspended animation," and as Sumaru lays unconscious, he dreams about when the Third Hoshikage comforts Sumaru about his parents' deaths, and tells him to be strong and to make his parents proud. Sumaru is rescued by Tenten and Rock Lee. Shortly after, Sumaru is guiding Neji, Tenten,and Rock Lee, with the other Hoshigakure genin, to find the ninja that stole the star. They all find the ninja, who is actually Sumaru's mother. Akahoshi uses his jutsu to try to kill him. Akahoshi briefly attacks Natsuhi and wounds her. Naruto, Neji, Tenten, Rock Lee, and Akato, flee to an unknown destanation where Sumaru and Natsuhi rest.