Hotaru

is the granddaughter of the former leader of the Tsuchigumo clan, En no Gyōja.

Appearance
She has dark-green eyes and mid-back length blond hair and very large breasts. She wears a light-violet and white top, black shorts, a black skirt, black high boots and light violet wristbands. She is rather short, as shown when standing in front of Naruto.

Background
Hotaru met Utakata after he saved her, from a group of ninjas were actually after him. During the battle Utakata was wounded, and collapsed after it. Hotaru ran to her fort to get help to save Utakata. After he was healed, Hotaru asked him to become her teacher, to which Utakata wasn't happy about. Utakata reluctantly begins to teach her the Water Walking Exercise first, believing that she wouldn't master it. In the morning, she shows that she was able to stand on top of the water by training all night. Next, Utakata taught her Water Release: Violent Water Wave, once again believing that she would not be able to master it without water-nature chakra only to discover she does possess water-nature chakra.

Six-Tailed Beast arc
When a group of ninja came looking for the Tsuchigumo clan's kinjutsu, Tonbee had Hotaru, along with Utakata, take the clan's forbidden jutsu so that ninja could not retrieve it. While traveling, Utakata got upset at Hotaru for calling him, at which point Naruto arrived, believing Utakata to be attacking Hotaru. Hotaru broke up the fight and Utakata left her, deciding that Team 7 would be capable in protect her. As she watched him float away in a bubble, she tried to convince him not to leave, but was unsuccessful in doing so.

While on the way to the clan's secret village, Naruto argues with her only for Yamato to devise a plan to convince Hotaru to accept their protection. Using his unique jutsu, Sai drew mountain leeches to fall on Hotaru, who freaks out and becomes afraid, causing her to accept Team 7's protection. When they reached the village, Team 7 leaves Hotaru with Tsuchigumo clan and Hotaru thanks Naruto before he leaves.

She is then brought to a personal room, unaware that the village had already betrayed her to the bandits from earlier. After tricking them with a bomb disguised at the secret jutsu scroll, she retreated into the forest, where she was soon captured again. Fortunately, Utakata arrived and successfully escaped with her. Later, sure that they were safe, Utakata had then rest by a waterfall. While Utakata merely insisted he was interested in the secret jutsu, Hotaru was sure that he did to save her. Once again, Hotaru begged Utakata to take her on as student, despite his obvious refusal, she insisted he had a to take her. When asked why she was so determined to learn under him and protect the school, Hotaru explained that it was the final wish of her grandfather and first master as it was this jutsu that could help restore the Tsuchigumo clan. To better illustrate her point, Hotaru partially removed her robe to show Utakata something on her back, which horrified him. Before they could continue talking, Kiri ANBU arrived and took Hotaru hostage. While Utakata was distracted, the ANBU acted quickly and restrained him. It was then revealed that Utakata was a missing-nin from the Kirigakure who killed his former master. Fortunately, Naruto arrived and took out one of the ANBU with a clone.

Trivia

 * means firefly.