|Alias||Thunder Beast of Kouka|
|Previous Occupation||King's 4 Great General|
|Previous Affiliation||Royal Palace|
|Relatives||Son Mundok (adoptive father); Tae-Yeon (adopted little brother)|
Hak, or Son Hak (ソン・ハク Son Haku) as he was known at the beginning of the story, is an adopted child of Son Mundok of the Wind Tribe. He starts off the story as the Wind Tribe General, as well as Yona's wise-cracking childhood friend and bodyguard who happens to be in love with her. He is very strong, known to people to be the "Thunder Beast of Kouka". When Soo-Won kills Emperor IL, Hak takes Yona and escapes from Hiryuu Palace.
Hak is a tall, well-built man with black hair and blue eyes. His main outfit is blue and grey with a dark blue overcoat. He carries around his signature weapon on his back or over his shoulders.
In flashbacks, it becomes known that Hak, Yona, and Soo-Won had all become childhood friends at one point, though the exact age this was at is unknown (perhaps age 13 for Hak and age 11 for Yona, as illustrated by the author). However, by the age of 15, it is clear that Hak is in love with Yona, who surprisingly is mature enough to recognize his own feelings at this time. In turn, Hak also knows that Yona is in love with Soo-Won, which irritates him.
During this period in their lives, Hak officially became Yona's bodyguard when he defends Yona from the Fire General's son, Kang Tae-Jun, and his advances. By the age of 18, Hak had already reached the status of Commander of the castle guards and earned the title of "Thunder Beast" or 'raijuu'. Added to this list of titles is 'Chief of the Wind Tribe', making him one very young and accomplished person.
Yona - Hak shares a close friendship with Yona, unbeknownst to Yona though, Hak shares romantic feelings for her ever since they were young. In the past, he has grown to destroy these impulses of doing anything outside the friendship line but every now and then, Hak can't help himself to showing his love her. He feels overprotective of Yona and often teases her to try to get her to do what he said. They also get in arguments, as Yona felt the need to learn how to fight with a sword to which Hak refuses to. When asked by Yona to just call her Princess Yona for her own selfish reasons, Hak kneels down and accepts her request, meaning she'd do pretty much anything for her. Hak has also been shown to brutally attack someone if they had ever attacked Yona, physically and/or mentally.
Mundok - Hak was adopted by Mundok as an orphan. They share a caring, yet casual relationship. Hak refuses to call him Grandpa with Mundok and also refuses to hug him when they see eachother. Though when Hak is ever being disrespectful, Mundok won't hesitate to discipline Hak.
Soo-Won - Hak and Soo-Won share a complex relationship. As kids, they were great childhood friends, and both loved to spar with each other. Hak cares for Soo-Won to the point that he's willing to give Yona to Soo-Won if they're happy, however, that friendship has quickly evaporated as soon as Soo-Won killed Yona's father, Emporer Il, whom he shows fierce loyalty too, especially since Yona has seen the death with her own eyes. As of recently, when Hak saw Soo-Won, he felt the urge to kill him and had to be pulled back by Jae-Ha, however, even Hak punched Jae-Ha just to get to Soo-Won.
Emporer Il - Hak thinks of Emporer Il as a 'bubbly' king who is a coward at first, however, in Chapter 3, it is shown that Emporer Il is actually not a coward once he grabs the blade of the sword of Kang Tae-Jun. This leads to Hak respecting him and creates an immense loyalty to the royal family.
Hak's spear fighting skills are the best in the country. His speed and strength allow for powerful blows to be dealt, even strong enough to sweep aside a large area of fog with one swift strike. Kija once observed that his strength could be on par with his own power. Even without his weapon, he can deal strong blows with his fists.
Hak is also very knowledgable of the areas in the land of the tribes, being a general of the Royal Family, and has been proven useful during their journey in finding the four Dragons. He is also skilled in swordsmanship and archery, in addition to the spear.
One of his more defining attributes is his stalwart heartiness, first shown when enduring a bite from a poisonous snake when protecting Princess Yona. That being said, this may be mostly due to his determination to live and protect Yona, both out of loyalty to the King and the Princess, as well as love.
- In the planning phase of Akatsuki no Yona, Hak’s original name was “Soron”. It seemed too similar to “Soo-won”, so it was changed to “Hak-jin”. In the end, it was shortened to “Hak”.