There was never meant to be a focal point of One Direction, no singular force, no megastar or breakout member. They were presented as the antithesis of the boy bands who came before them -- there is no well-oiled machine here, just a group of singers who cavort about stage like a colony of feral cats whose legs have been untethered for the first time since birth. There is an undeniable charm about their candor, something palpable but unexplainable that screams "One of us!" to their legions of fans. One Direction are the every man, and the every man that every girl wants. They do a good job demonstrating a united front. It's part of their appeal.

But we would be deluding ourselves if we denied the sheer magnetism, charisma and charm of their media-appointed, unofficial frontman: Harry Styles. Teenagers have constructed shrines alongside a Los Angeles highway that was once laden with his vomit, they have collected said vomit in an attempt to sell it on eBay, they have lost their breath near him, certainly their words. Every fan account, press account, 20-second meet-and-greet, points to his being respectful, generous, kind, alluring. In short? Harry knows exactly what he's doing.

So when asked to celebrate the 21st birthday of a boy who was hardly on the world's radar five years ago -- a milestone, for sure -- it proved to be a difficult task. How, exactly, do you sum up the full parts of Harry Styles -- those which make grown men and women weep and drool and salivate over -- without sounding a little bit crazy, crazy, crazy? Can it be done? Short answer: No. Long answer: We'll try.

The reality is Harry's appeal is, somehow, transcendent of age and gender. You may not like or respect One Direction (yet), but you probably think Harry Styles is an alright guy. But why is that? How did he go from floppy-haired boy wonder to cavorting with the likes of Kelly Osbourne and Rod Stewart, yet still maintain his mass appeal?

Fans track his every move, but no one ever understands what Harry's tweets really mean and he has this oddly monotonous way of speaking. He regurgitates words and phrases with the similar pace of a turtle struggling through a pit of molasses. Harry is the king of constructed mystery, yet he somehow manages to remain endearingly humble and, dare we say, real.

And that's the rub, isn't it? The problem with most celebrities is the juxtaposition of their human faults with their otherworldly public personas. When they don't make mistakes, we don't trust them. When they do make mistakes, we tear them down. It's hard to strike the right balance between the two. The thing with Harry is, we saw his celebrity happen; it feels a little less manufactured a transition. Harry was not delivered to the public sphere dressed to the nines in Burberry and Givenchy. He wore ill-fitting, baggy clothes. He had an awkward stage. He really was one of us. They all were.

Let's take a look back, shall we? Once a cowl-neck connoisseur with a flair for bow-ties and blazers, Harry -- perhaps inspired by the moth permanently emblazoned across his abdomen -- slowly morphed over the course of two years, emerging from his cocoon as a tattooed hipster, complete with greasy man bun and heeled, glitter boots.

Harry is decidedly corny, listens to dad-rock, hangs out with old guys. Harry helps fans propose to their significant others, he became a public supporter of Emma Watson's campaign for gender equality, supports gay marriage. He boasts about watching 'The Notebook' with friends -- no irony or sarcasm attached. Are these characteristics everyone should possess? Absolutely. Harry shouldn't get a gold star for being decent, for doing the bare minimum. But in a world where one's bro-ness continues to be held up as the standard, the pinnacle of masculinity, we get why it matters.

These are all things observed by the fandom at large, things that have further endeared the common One Direction fan to Harry -- as though we needed more reasons to fall further into the spiral that is loving a member of the world's most popular boy band. In the long run, none of this matters. We are all jumbles of nerve-endings, bone and sinew; we create our own realities. And in the world of the teenage girl, Harry reigns supreme.

In a pop landscape where the '80s throwback is more electronica than anything else, One Direction opted for the cheesy rock route with their latest release, 'Four.' We can't pin this evolution in their sound on Harry, specifically, but he is undoubtedly the rock star of the group. He posts Nirvana photos on Instagram, was spotted at a Fleetwood Mac concert, dates older women, younger women, every woman. He has that throaty growl that propels him beyond Miscellaneous Boy Band Member status. If Liam is One Direction's patriarchal figure, Harry is their bad-boy-with-a-heart-of-gold. Taylor Swift's pinnacle of pop perfection, the tour-de-force that is '1989,' wasn't written about anyone specifically, alright, sure. But Harry is every bit the James Dean daydream she hints he is -- long hair, slicked back, white t-shirt? Sure, we'd let him take us home, too.

It isn't often you feel as though you're going through a second puberty. That being blown kisses across a stadium floor by some long, lean mishmash of limbs and ink and hair -- five years your junior no less -- who probably can't see past the blinding stage lights anyway, would be enough to send you screaming in all caps to Twitter. But for those of us over the age of 18 who fell so fully for One Direction at one point in time, that's exactly what it's like. And when Harry is your fave, you feel it all the more.

And so, we extend a very happy 21st birthday wish to the indelible Harry Styles. I recently celebrated the fifth anniversary of my legal ability to drink, so I'm right there with you, Harry. I'd say the drinks are on me, but let's be real, they should totally be on you.

See Photos of One Direction Through the Years!

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