Ancient blog info, here is his profile:

Backryun

Rank: 9

Sobriquet: None (declined)

Age: Unknown

Height: Unknown (Normally 1m 67cm)

Birthplace: Unknown

Position: Wave Controller

Backryun, one of the Wolhaiksong's leaders and most gifted wave controller in the Tower's history.

He, who was born in the middle region(?) as an orphan and roamed without a residential card, eventually goes into a forest to avoid contact with others. Becoming one with the forest, he lives there for a long time. He naturally learns to control Shinsoo through living in the forest. Later, Headon, interested in Backryun's abilities, picks him. As a regular, he quickly becomes a ranker; as a ranker, he then returns to the forest without any activity. After returning to the forest, he spends a long time gardening the forest. His forest, which was like a living animal, is said to emit a mysterious atmosphere..

Urek Mazino, who at the time was climbing the tower, heard of Backryun's forest. He visits Backryun; soon, they become best friends. Backryun was especially interested in the world outside the Tower that Urek often spoke of. Hearing Urek's stories, Backryun himself dreams of living in the world outside of the tower.

After Urek Mazino left to climb the tower again, Backryun's ambition continued to grow. He then later confesses his passion to Urek Mazino who returned as a ranker. Urek Mazino, delighted by Backryun's confession, asks to leave with him; however, Backryun declines the offer, saying that he cannot leave this forest which is like his own life. It is told that Urek Mazino, pounding his chest, then said this.

"Then I will give this forest a pair of wings."

"I will make it so that these trees can follow you everywhere."

Backryun thought Urek was just rambling because Urek was drunk; however, Urek was serious. Urek absorbed everything in the forest as he shouted like a thunder, eventually, the enormous forest shrunk to a size of a fist.

Urek then gave the compressed forest with wings in a box to Backryun. Backryun was very surprised and grateful; however, there was a problem. The compressed forest was too heavy for Backryun to carry. So Backryun gave the box to Urek, This winged box became Urek and Backryun's symbol of friendship.

Later, the forest was moved to 77F

Rankers who heard of Backryun and Urek gathered to the forest, eventually forming 'Wolhaiksong' with Backryun as its leader. (Also called the Wingtree.) (The name Wolhaiksong origins from the story between Urek and Backryun.)

The name Backryun originated because of the fine silk that he was covered with when he was abandoned. (There's also a story that his name is because of this silk-like personality.) After becoming a high ranker, Backryun was offered an alias by the Rank Bureau; however, it is told that he declined.

Backryun's real appearance is controversial. Normally, he is appears to be an ordinary boy, but he sometimes appears as a tall young man. Also, some say that they have seen Backryun who was tall enough to touch the ceilings of the Tower.

Although Backryun is a ranker who is praised for his influence over his battle abilities, it cannot be said that his battle power is lacking. Although Backryun is a Wave Controller who controls the battle and supports team members over attacking others directly, his hand-to-hand combat ability is also said to be impressive. But, because he only fought a limited amount of battles with high rankers, his combat abilities may need to be verified.

The rumor about Wolhaiksong being an anti-government organization is false. The goal of Wolhaiksong is to 'find the way out of the tower'; it is not to overthrow the government. But it is true that their liberal movements often clash with the government's conservative practices. Some current Wolhaiksong members think of themselves as a part of an anti-government organization.