Chihiro: Will we meet again sometime?
Haku: Sure we will.
Nigihayami Kohakunushi (ニギハヤミ コハクヌシ, Nigihayami Kohakunushi, lit. "god of the swift amber river"), referred throughout most of the film by his nickname Haku (ハク, haku), is the deuteragonist in the Japanese animated film Spirited Away.
Haku appears to be around 12 years old in physical age. He has straight, shamrock green hair in a bob haircut and slanted, shamrock green eyes when he is human. Haku wears a short, turquoise blue hakama, white kariginu with a turquoise blue kimono underneath and beige sandals. When he transforms into his dragon form, he has a mint-green mane and a white, scaly body.
Haku first appears when Chihiro Ogino is on the bridge to the Bathhouse. At this, he quickly tells to her to get out of the town and get back across the river before nightfall. But when Chihiro fails to do this, she runs off. Then, in a panic, he goes to search for her and tells her that she is becoming invisible, he then gives her something to eat so she won't disappear. Haku then unbinds her when her legs become stuck and takes her to the bath house. Then, he helps her cross the bridge and in the garden outback, he tells her that she needs to get a job to survive from Kamajī, the boiler man.
After Chihiro succeeds in getting a job, Haku then hands her off to Lin. The next morning, he takes her to her parents, who have been turned into pigs. Haku then warns Chihiro that if she forgets her real name like he forgot his, then she will be trapped in the spirit world forever. Then, Haku leaves and comes back days later, gravely injured by paper birds and blood dripping from his body. Now, Haku ends up in Yubaba's office bleeding and close to death. Having Chihiro on his back, they end up falling down a shaft and into the boiler room with Kamaji.
Then, while Chihiro is off returning the seal that Haku allegedly stole, he tells Yubaba that he will get her son back and flies off to Zeniba's (Yubaba's twin sister). Zeniba then tells them that only true love can break the curse. Flying in the night with Chihiro on his back, Chihiro tells him that when she was little she fell into a river to retrieve a little pink shoe and that she thought she would drown, but, he saved her. She continues and says the river's name was the Kohaku river and thus revealing his real name. Both of them return to the bath house, and they say their good-byes at the river which has now been filled in.
Haku promises, however, that he and Chihiro would one day meet again as he lets go of her hand and watches her leave to go find her parents.
Haku is a lean-built twelve-year-old boy and, as Yubaba's apprentice, he is second in command at the spiritual bathhouse. Haku is not an ordinary human. He is a spirit being who has the ability to transform into a dragon.
He is able to fly all around the Spirit Realm, running multiple errands for Yubaba. He also shares great spiritual knowledge. Haku has sharp green eyes, along with a black, traditional Japanese bob cut. He wears blue pants, called a monpe, a white Japanese kimono and a blue sash tied along his waist. His dragon form consists of a snake-like body with antlers and long whiskers. It has silver scales, and a turquoise mane. He is able to change between his dragon form and human form at will.
Haku has multiple personalities. He can be kindhearted and supportive at times, strict and high-strung at other times. He is wise, and is able to act accordingly to the situation. He is more than willing to stick his neck out when he cares about someone. From the beginning of the story, through to the end, he does everything within his power to keep Chihiro unharmed and to help her leave safely. His steadfast resolve helps Chihiro finally trust him, amidst contradictory information from other Spirited Away characters about him.
Of course, Haku always said she could trust him. Lin, however, was not sure of Haku's intentions. Yubaba's twin sister, Zeniba insisted that Haku is a greedy thief, who had stolen her golden seal. In the end, Chihiro puts her faith in Haku. Later on, it is revealed that Haku is Yubaba's slave, who controlled him with a black worm in his body.
As a river spirit, Haku possessed supernatural powers that are primarily associated with the element of water. Examples of powers he was shown to possess are:
- Asian Dragon Physiology: Due to his being a Japanese river spirit, Haku has the ability to take on the form of an Asian dragon, and was shown to be able to fly in this state.
- Arcane Knowledge: Due to his status as a river spirit, as well as being Yubaba's apprentice, Haku possesses an extensive knowledge of magic and the spirit world, which he regularly used to keep Chihiro out of trouble and, ultimately, free her and her parents from the spirit world.
- Flower Petal Manipulation (possibly): Though it was never specifically confirmed, it is possible that Haku has the ability to create, shape and manipulate flower petals - when trying to help Chihiro escape the spirit world during their first meeting, he blew petals from his fingertips to serve as a distraction from those who might have sensed her presence.
- Spell Casting: Haku has the ability to cast spells, allowing him to alter reality to various effects - he used a spell to enable Chihiro to regain the use of her legs while she was still adjusting to being in the spirit world.
- Telekinesis: Haku has the ability to move objects with his mind, which he channeled through his hands - while he was trying to escort Chihiro to safety, he opened doors at a distance merely by gesturing at them with his hands.
- Cloaking (limited): Haku has the ability to hide the presence of oneself or others, preventing others from detecting or discovering one's location. However, this ability is shown to be limited - when Chihiro took a breath out of sheer shock at seeing Aogaeru, Haku's cloaking over her was broken, enabling Aogaeru to identify her as a human through her scent.
- Force-Field Imprisonment: Haku has the ability to bind, or imprison, or stop objects and individuals by using forcefields - when Aogaeru tried to attack Chihiro when she was exposed as a human, Haku stopped him by imprisoning him in a forcefield.
- Flight: Even when in human form, Haku has the ability to defy gravity and propel himself through the air at tremendous speeds and heights.
- Memory Implantation: Haku has the ability to implant memories in others' minds, which he used to guide Chihiro to secure a job at Yubaba's bathhouse.
- Supernatural Cooking: Haku has the ability to cook anything with supernatural or magical properties - during his and Chihiro's second encounter, he fed her a berry that enabled her to take corporeal form in the spirit world, and, much later on, he fed her rice cakes that enabled her to regain both her physical and mental strength, as well as to retain her optimism.
Haku means white like the color of his dragon form and his clothing. He wears a hakama, a clothing of the Shinto priest. He speaks very politely and is noble, which indicates his origin as a deity. He calls himself watashi instead of boku.
Nigihayami Kohaku Nushi is his real name. In the film, he just calls himself Kohaku river for short. He forgot his real name a long time ago, because the Kohaku river got shut down.
- Nigihayami implies his noble lineage nigi haya hi no mikot.
- Kohaku means amber.
- Nushi means spirit.
- The name "Haku" means "white" (白), while the name "Kohaku" means "amber" (琥珀).
- Haku is the only character in the film able to turn into a dragon at will.
- As he once served as Yubaba's apprentice, he likely has similar magical skills as she does.
- The river he resided in was filled in with apartment buildings, according to Chihiro.
- It is unknown if Haku can still turn into a dragon after regaining his lost name and memories.
- Yubaba threatened Haku with killing him if she set Chihiro free if she found her parents in a group of pigs. In the English translation, Yubaba said instead Chihiro had to stay at the Bathhouse forever.
- In the close-up of Haku, you see his shining eyes. This idea came from Hideaki Anno, because he refused Hayao Miyazaki's offer to draw Haku transparent.
- He bears a resemblance to Akira Toya from Hikaru NO Go.
- "You shouldn't be here."
- "Get out of here now!"
- "It's almost night."
- "They're lighting the lamps."
- "Leave before it gets dark."
- "No, but for some reason, I remember yours"
- "Don't be afraid."
- "In the name of the wind and water within thee, unbind her."
- "Get up."
- "I'm back from my mission."
- "Three days of our food and her smell will go away."
- "It's about my mission, right?"
- "Wait a minute."
- "You haven't noticed that something precious to you has been replaced."
- "Yeah, I remember being in darkness."
- "You did it, Chihiro!
- "I remember you falling into my river and I remember your little pink shoe."
- "If you don't get a job, Yubaba will turn you into an animal."
- "Even the tiniest breath will break the spell, and then everyone will see you."
- Cf. Kojiki, trans. Donald L. Philippi (University of Tokyo Press, 1995  ), page 531.