In кσяєαn, “oppa” is a term used by women to address an older man, but only within close relationships such as an older brother, a close senior, or a close male friend—or in an intimate romantic relationship such as a boyfriend or husband. However, among Hallyu or K-pop fans, it has become an everyday word used to refer to idols. Especially regardless of age, “All handsome men are oppa” has become a kind of philosophy within the fandom community.

Applying this philosophy, some ARMYs called Jungkook "oppa" despite the fact that he had debuted with BTS at just 15 years old and was often seen as the group's "baby." His handsome looks and mature-for-his-age appearance simply made it too hard for them to resist. Meanwhile, in BTS's early years, Jungkook seemed to prefer being called "baby" and was shy about the nickname "oppa." At a 2015 fansign, when ARMYs chanted "oppa," the then-17-year-old even firmly replied, "I am not your oppa, stop calling me oppa," even joking that he would check fans' IDs to see their birth years.

However, at least over the past four years, things have almost completely reversed: Jungkook himself confirmed that he had grown up, rejected being called a baby, and naturally embraced the nickname “oppa,” repeatedly sending fans into a frenzy.

The first shot came from a Weverse post on September 2, 2022, one day after his 25th birthday. A fan shared a post saying, “Because you know I love you: Well, you're a baby so how about a sunscreen for babies???” Under the post, Jungkook bluntly replied, “Ahem I am not a baby!!!”, officially declaring an end to his youthful era.

The second shot—piercing straight into fans’ hearts—came from a post on November 4, 2025, a few months after he was discharged from the military. During that period, Jungkook frequently held live broadcasts almost every day. That day, as usual, fans waited until they received a notification from Jungkook on Weverse.

In his message, Jungkook wrote: “I couldn't turn on the live early cause of the treadmill installation at home today and I had to go for some re-recording as well. Also, we are doing the kancho opening today. Oppa purchased new camera and lighting too. See ya in the evening.”

The key point was not the delay of the broadcast, but the fact that Jungkook referred to himself as “oppa” in the sentence “Oppa also bought a new camera and new lighting,” instead of simply using “I” or another neutral pronoun. This meant that after nearly a decade, ARMYs had finally received “official permission” to call him by that affectionate title.

The phrase “JUNGKOOK OPPA” even quickly topped the trending charts on X (formerly Twitter) in кσяєα at the time and became a hot topic across online communities. Just one sentence of Jungkook officially confirming himself as “oppa” drove fans crazy because it felt so masculine and romantic. The once-shy boy had truly grown into a confident and charming man.

Especially throughout the recent ARIRANG World Tour concerts, while many moments continued to prove that Jungkook is still BTS's adorable maknae, fans spent much of the tour flooding the comments with cries of "oppa" as videos highlighting his mature charisma went viral. One standout example is this clip, which has already amassed nearly 1 million views:

Fans still vividly remember the moment they were completely captivated by Jungkook, expressing:

- Remember the time when he got real mad when someone called him oppa?! Hahaha.. he has finally accepted it

- Feels like I graduated. Bye bye baby Jungkook, welcome Jungkook oppa lmao

- First he rejected being called "baby". Then, he called himself oppa on his own will. OMG, my man

- back in my days he hated to be called oppa omg my boy is so hilarous and cute

- Why do I feel so old? I lived through the days when he hated being called "Oppa," and now I'm living through how he's come to love it

- back when he would throw hands at someone calling him oppa, my man is grown

- I bet he was sitting there giggling knowing exactly what it would do to us

- Oppa"..."see you this evening".....Jungkook, are we dating?

- how did we go from don’t call me oopa to "i am not a baby" and "Oppa see ya in the evening". I even fall deep into this delulu

- Parasocial relationship has become so strong he started calling himself oppa

- I feel like jk is my bf who cling to me like the last 2 days I am having breakfast, lunch, even napping with him..I think Armys are dating him

- If you'd tell me few years ago that jungkook would refer himself as oppa in 2026 I would've laughed at you