Shinhwa fans. We all know at least one. But, compared to the fans of other idol groups, there is something very special about them.

It's hard to put your finger on it exactly. Is it that they are shy about admitting their bias at first? Or that they have been dedicated fans for over a decade? Maybe it's the unique ways they show their love?

Admittedly, I had never really thought much about Shinhwa until this year with their 15th anniversary. I admire that the group has had continued success after so many years. I like that when you look at how Shinhwa has changed over the years, it fits with the times. They may have been around longer than any other K-Pop group, but they are still just as relevant as when they first debuted.

But maybe what I like the most about Shinhwa are those special fans of theirs.

Go to a Shinhwa concert (if you're lucky enough to get tickets, that is) and you will see a very diverse crowd. Old and new fans of all ages, shapes, and sizes - and all with one very important thing in common: the idea that Shinhwa has always been, and will always be, the best.

I didn't think I knew any Shinhwa fans until I was working on a piece about the 15th anniversary concert in Seoul this past spring.

I was taking a break and skimming through Facebook when I saw a post from a close friend of mine - she was smiling ear-to-ear and holding a bright orange Shinhwa sign. I instantly messaged her.

This is the point in our more than three-year-long friendship when she revealed that she is, in fact, a die-hard Shinhwa Changjo and has been since she was very young.

"When I was in middle school, I saw Shinhwa for the first time. I was so impressed by the fans that I wanted to join them," she explained. "And the Shinhwa members have so much charisma! Even now, they still continue to make an effort."

The same thing happened with my roommate. Knowing full well what my job is, she didn't tell me about her almost life-long obsession with Shinhwa until two weeks before she moved out.

The next day, she even told me that when she confessed to some other Shinhwa Changjo that she had revealed her bias to me, they scolded her saying that I "wouldn't understand."

And this got me thinking, why are Shinhwa fans so shy about their love?

"Shinhwa and the fans believe we have a special relationship," explained my friend. "It's a matter of respect."

I get that. This is probably why you don't see girls walking around decked out in orange with 'Shinhwa' tattooed on their faces.

But it doesn't mean they don't have their own ways of infiltrating the minds of non-fans with their bias.

Recently, those clever Korean netizens have been hard at work sifting through K-drama episodes to find evidence that the writers are closeted Shinhwa Changjo.

Two specific television shows come to mind, 2009's Boys Over Flowers and the currently airing I Hear Your Voice.

The Boys Over Flowers writer was a bit obvious with her fan status. The character's attended Shinhwa High School, Goo Junpyo's family's company was named Shinhwa Group and had an orange company logo.

While those examples are blatant, there are countless other hidden clues that only Changjo would recognize - including certain phrases, names, and locations.

The writer for I Hear Your Voice may have tried to hide her fan status at first, but things are now getting a little excessive. She appears to have a really strong affection not just for Shinhwa, but for member Shin Hye Sung especially.

Like the Boys Over Flowers writer, naming characters or places carefully is one way to interject with fan bias. The female lead is Hye Sung and her mother's restaurant is called Hye Sung Chicken. The twins' names resemble the singer's given name as well.

Some clues, like names, are very obvious, while others only Shinhwa fans would understand.

The careful use of numbers - Min Jun Guk's criminal ID number is the same as Shin Hye Sung's birthday - or the main character's affinity for a certain food - she pours sesame oil all over each meal - are more examples.

Even written clues abound in I Hear Your Voice - newspaper headlines including 'Shinhwa,' or on-screen text messages that include members' nicknames.

The scripts themselves are even orange!

Whether they hide their participation in the fandom or sneak it in to their work somehow, Shinhwa fans really do have a unique way of showing the love - making them some of the most impressive fans on earth.

Don't believe me? Here is how my former roommate described her passion for Korea's longest-running boy band: "I feel like they are my family and life. I can't explain my life except them."

(ed's note: Is there another fandom like this one? FTISLAND's Primadonna perhaps?)