Kim Hyang-gi Reveals She Called Yoo Yeon-seok 'Uncle' on Set at Age 14 — And He Knows Exactly Why

Kim Hyang-gi is 24 years old now. She was 14 when she filmed A Werewolf Boy alongside Park Bo-young and Song Joong-ki. On the set of that 2012 production, she addressed Song Joong-ki as "oppa" — the warm Korean term for a slightly older male — and addressed Yoo Yeon-seok, also in the cast, as "삼촌." Uncle.

Yoo Yeon-seok's reaction when Kim Hyang-gi shared this story was immediate: "I had a 2:8 parting hairstyle at the time. That was not an oppa hairstyle." He was laughing. Kim Hyang-gi nodded. "But you were always smiling after cut," she said, "even though you played the villain."

The exchange happened on Yoo Yeon-seok's YouTube channel 주말연석극 (Weekend Yeonseok Theater), during a promotional visit by Kim Hyang-gi and her co-star Cha Hak-yeon — known as N from K-pop group VIXX — to promote their upcoming Coupang Play drama Absolute Value of Romance. The video, uploaded April 4, accumulated views quickly among fans of both the actress and the channel.

A Werewolf Boy and the Set That Shaped Her

A Werewolf Boy (늑대소년) was released in October 2012 and became one of the year's most beloved Korean films. The story follows a feral young man — played by Song Joong-ki — taken in by a rural family, who forms a tender bond with their daughter, played by Park Bo-young. Kim Hyang-gi played Sun-ja, the daughter's younger sister — a memorable supporting role for an actress who was only in middle school at the time.

Yoo Yeon-seok played Ji-tae, the film's antagonist: cold, calculated, the source of most of the story's external conflict. That he was apparently warm and upbeat to the child actors between takes — always smiling after the director called cut, despite playing someone genuinely threatening on screen — is the kind of detail that speaks to how film sets in Korea tend to operate, and why actors like Yoo Yeon-seok build the long-term relationships they do.

The 2:8 parting, for those who need context, is a deeply center-parted hairstyle that in Korean cultural shorthand reads as bookish or conservative rather than casually attractive. Yoo Yeon-seok's self-deprecating acceptance of the "uncle" designation — while clearly charmed by it — was exactly the kind of moment that plays well on YouTube: genuinely funny, a little vulnerable, and impossible not to share.

From Child Star to Leading Lady

Kim Hyang-gi's career since A Werewolf Boy has been deliberate and unusually wide-ranging. After a series of acclaimed child and teen performances, she stepped decisively into adult roles with Innocent Witness (2019), a courtroom drama opposite Jung Woo-sung that earned her the Grand Bell Award for Best New Actress and established her as a performer capable of carrying serious dramatic material without support from a more established co-lead.

Later roles in Joseon Psychiatrist (2021-2022) and the Netflix series Cashero (2025) have extended her range further into historical and genre television. Absolute Value of Romance marks her first time leading a high-teen romantic comedy as an adult — a deliberate departure from the serious work she has built her reputation on. Early promotional material suggests the shift is working.

The Double Life of Yeo Eui-ju

Absolute Value of Romance (로맨스의 절댓값) premieres April 17, 2026, at 8 PM KST on Coupang Play in Korea and Amazon Prime Video internationally. It is a high-teen romantic comedy directed by Lee Tae-gon — whose previous work includes Hello My Twenties (청춘시대) and True to Love — with a script by Lee Min-joo.

Kim Hyang-gi plays Yeo Eui-ju, a high school student living a carefully maintained double life. By day she is an ordinary student — quiet, unremarkable, invisible in the way many teenagers prefer to remain. At night she is "Lee Muk," the pen name of a wildly popular online BL romance novelist whose serialized fiction has accumulated a devoted readership with no idea the author is a teenage girl writing about her actual teachers as characters.

The BL novel's subjects are four of her school's most attractive teachers, each inspiring a different character in her ongoing story. When Yeo Eui-ju's secret identity is accidentally exposed at school, she faces potential expulsion. When she begins, unexpectedly, to develop real feelings for one of the teachers who inspired her fiction, the situation becomes something she cannot simply write her way out of.

It is a premise built for a performer who can play genuinely flustered without sacrificing intelligence — embarrassed but clever, panicked but resourceful. Kim Hyang-gi has not been asked to do this before in her career. The teasers suggest she has found the frequency quickly.

Cha Hak-yeon and the Cast

Opposite Kim Hyang-gi is Cha Hak-yeon — known internationally as N, VIXX's leader — as Ga Usu, a math teacher with an IQ of 156 and Mensa membership. The character is, within the show's logic, one of the primary inspirations for Yeo Eui-ju's BL fiction — which creates an immediately complicated dynamic once her real feelings become clear.

Cha Hak-yeon has been steadily building an acting career alongside his music work. His appearance alongside Kim Hyang-gi on the Yoo Yeon-seok channel — relaxed, genuinely funny, easy in the promotional setting — suggested the kind of comfortable rapport that tends to translate well to screen chemistry.

The supporting teaching cast includes Kim Jae-hyun as a Japanese language teacher, Son Jeong-hyeok as a PE teacher, and Kim Dong-gyu as a Korean language teacher. The show is co-directed by Kim Jun-hyung alongside Lee Tae-gon.

From Uncle to Leading Lady

There is an arc in the Yoo Yeon-seok channel appearance that works whether or not anyone planned it: the girl who called this man "uncle" at 14, on the set of a film that would become one of that year's most beloved, is now 24 and appearing on his YouTube channel to promote a romantic comedy where she carries the story.

Kim Hyang-gi mentioned this directly in her characteristically straightforward way: "You were always kind on set. I learned a lot from the people around me in those early years." Yoo Yeon-seok, still processing the uncle revelation, was visibly touched — and clearly relieved that the 2:8 hairstyle had been accepted as sufficient explanation.

It was a brief exchange in a longer promotional video. But it was the kind of moment people clip and share — not because it was dramatic, but because it was warm and specific and true in the way the best stories from Korean entertainment tend to be.

Absolute Value of Romance premieres April 17, 2026, on Coupang Play in Korea and Amazon Prime Video internationally.