Hwi Lee is the 18-year-old leader of the rebels against the government, and known across the country as the Crimson Moon. He is also known as a highly valued painter named Hong, with his rare paintings costing a hefty sum to those who buy them.
King JinWon believes that the Crimson Moon is none other than Crown Prince JinYon, who escaped from JinHee Palace 10 years earlier during the coup where his mother YonRi Yoon assassinated Queen AnYoung. JinYon means Crimson Moon in Chinese characters.
Hwi Lee is a young, attractive man with long blue-black hair, tied back in a low pony tail, and emerald green eyes. He wears a basic men's hanbok with khaki trousers, dark blue jokki, wrist guards, and sandals. He is also fairly androgynous.
Fairly focused on his goals, Hwi Lee also has an occasional curious side. He first and foremost strives to keep his real identity unknown and not interfere in other people's lives if it is not necessary, however this goes more to protecting those he is close to. As a leader of the rebel army, he cares very much for his country and his people. He is not afraid to do the right thing, and does not like when his comrades get hurt. He will not hesitate to fight to kill (as Crimson Moon) if needed. When it comes to Danah, he is very passive and selfless, never correcting her about mistaken identities.
Note: Parts of the History section contains major plot reveals from Episode 90 and beyond.
In flashbacks, the author employs misdirection to lead the reader into making incorrect assumptions about the identity of Crown Prince JinYon. Most readers will assume that he is Hwi Lee before Episode 90, where he is revealed to be Juk Lee.
Queen AnYoung gave birth to twins, Juk Lee, and Hwi Lee. Hwi Lee was sickly when born, and when King Hyul Jin heard that his wife birthed twins, he grew fearful. The King had killed his own twin brother in the past for the throne, and wanting to avoid future bloodshed, he ordered that the doctors refuse all treatment for Hwi Lee. One of Queen AnYoung's maidservants overheared this order, and she alerted the Queen immediately. The Queen was angered, but did not have any power to do anything, but then Ha Lee (her cousins husband) shows up to her chamber to congratulate her. She urgently explains her situation to him, and she begs him to flee the palace with Hwi Lee. He feels compassion for the sickly baby, who grabs his finger showing that he has the will to live, and he flees the palace. He bumps into Doctor Ma, and he begs him to forget what he saw, but Doctor Ma stops him. He decides to treat the sickly Hwi.
Hwi had been living with Ha Lee ever since the night he was born. One day the King has become sick and knows that his time is almost up. He calls Queen AnYoung, and reveals to her that he knew that Hwi was alive this whole time, despite her lying that Hwi had died due to the King abandoning him. He gives permission for Hwi to be brought back to the palace, under the condition that the Queen does not reveal his identity until Juk Lee is on the throne. So Hwi is taken to the palace, much to his excitement, and he becomes the companion of the Crown Prince, Juk Lee.
Hwi and Juk become friends quickly, even though Juk first protest against Hwi being brought to the palace, but this was due to him believing that Hwi would be used as a double for him, which would put Hwi in danger, and he states that Hwi's life is as important as his own. But SonWu SoeYin asks if Hwi could stay as his friend instead then, to which Juk happily agrees to. Hwi grows a strong relationship with him, and both consider each other to be like brothers. Hwi says to Juk that doesn't he have a brother already? Juk replies that he does, but he is not close to him, since the people in the palace forbid him to see him.
One day, Queen AnYoung visited Juk Lee, and Hwi Lee. She had brought presents for them, new cloths that she herself had made. The boys welcomed her, and then she rushed up to Hwi and hugged him, to his surprise. She thanked him for coming to the palace, and Hwi asks her why, as it is his honor to be able to live there. Queen AnYoung gives him this sad look, which he is not able to understand. She then presents her clothes to the boys, and after trying them on, they exclaim how they almost look the same. Juk then whispers to Queen AnYoung that the clothes she had made finally reached their owner, which she responds to with shock and a nervous face. Asking how he knew, Juk reveals that sometimes he would receive cloths that were a different color than the ones he saw his mother make, implying that this whole time the Queen had been making cloths for Hwi, even when he was living with Ha Lee.
The day that YonRi Yoon enacts a coup d'etat, Queen AnYoung hurriedly wakes Hwi Lee, and urgently tells Juk Lee to flee with Hwi, and asks them both to live. SonWu SoeYin gives them an amulet, and Juk flees with the confused Hwi. Assassins ordered to kill the Crown Prince follow them, and one is able to horrible injure Hwi Lee. Blood flows from his wound, and the two are forced to hid. When it became clear, Juk carried Hwi to YuHyang Ru. They hid there, but SolHwa Wol finds them, and she brings her mother to the scene. Juk begs YoungHwa Wol for shelter and help for the slowly fading Hwi, but she refuses, and says she will only provide shelter to him if he kills Hwi, and she throws him a knife. Juk takes the knife, and looking at Hwi, he decides to try to save him. Juk stabs his own eye, and begs forgiveness from YoungHwa Wol if his eyes had offended her, and begs her to just save Hwi. Touched by his loyalty, she grants his request.Hwi woke up a week or so later, and he was shocked to find Juk Lee is such a condition, with his eye covered with a bandage and his hair having turned white. He hugs him and cries, asking why he did that for him.
Nabi had been put into a jail cell, and Danah tries to help Hwi escape, but JinWon interferes and stops her. Later on he asks Nabi why she is his enemy, and expresses his jelousy towards JinYon, as he wonders why she wants a world where he rules, and not him. He asks her if she will leave JinYon and be his, and that he will grant any wish of hers, while admitting to her that he is twisted and only knows how to buy a persons heart. Nabi then replies asking him to hand the kingdom over to Prince JinYon, and JinWon calls her stubborn and laughs. He says that all he needs is her, and shows willingness to do so, but still can't understand what JinYon is to her. But Nabi then states that even then, he can never have her. JinWon replies that she is a fool, and if she had said yes, she could have killed him for the rebels because he would keep her by his side. He realizes that she had been trying to escape for him, and Danah had helped, and he says that everyone has been trying leaving him, but he asks her if she thought it would be easy. He declares that he won't let her go, and the only way to escape is for one of them to die. He then leaves Nabi alone.
Hwi is able to escape his cell, and he goes out to regroup with the rebels as the attack goes on. He then dons his mask as the Crimson Moon. He runs into JinWon, and the two fight. JinWon is able to overpower him due to Hwi's hesitation, and while he is pinned down, JinWon takes off his mask. JinWon becomes confused, frustrated, and sad, knowing that his only friend in the end was trying to kill him. Hwi stands still, hesitant and upset as to what he should do. Suddenly JinWon remembers Nabi, and rushes off to save her, fearing that she may be harmed in the rebellion. Hwi follows him as he stumbles over to the jail. JinWon searches the area, but is unable to find her, and turning around he sees her in the doorway. He runs to her and grabs her arms saying how worried he was that she would be hurt, but then he realizes that the one he sees is not Nabi, but Hwi. He breaks down crying, say no, and when he finally calms down, he says that whether he is is brother, his best friends, or even the love of his life, he will not give up and he will fight him to the death. He points his sword at Hwi, and challenges him to come. Hwi lifts his sword and rushes towards him, as they both swing their swords. Hwi stabs JinWon in the abdomen, and he exclaims why? JinWon drops his sword, asking Hwi why he hesitated, and Hwi wonders the same. JinWon says his last words and farewells, and Hwi begins to cry, but is unable to know why he felt so much sadness.
Danah stumbles in to the room, and she sees Hwi crying, and the dead body of JinWon. Her eyes widen in shock, and Hwi turns to face her, but suddenly an arrow pierces her in the back. Hwi panics and rushes towards her. He picks her up and carries her, while he himself becomes weak and injured. He eventually falls down in the midst of the battlefield, and he begins to lose consciousness. When he sees Juk Lee fighting, he notices a person attempting to strike him in the back, and he musters his strength and jumps between the two. Juk Lee turns around in shock and shouts his name, as Hwi finally passes out, thinking that he fulfilled promise.
After Juk Lee is put on the thrown, we later see Hwi alive, having run away without telling anyone where he was going. He carries the now crippled Danah on his shoulders, singing the lullaby they both knew, and he sits her down on a rock. She calls him by the name JinWon, and he turns to her with a smile, though he looks sad.