In the vast ocean of bizarre Reddit communities, there exists a subreddit called r/OneTrueDiggle. It’s not as weird as other forums, but in it, you’ll find fans of the CW series Arrow referring to the show’s handsome John Diggle, played by David Ramsey, as a “savior.” As one might expect, the subreddit is full of memes and YouTube music videos devoted to him. They dig him — big time. On a live broadcast of WWE RAW last year, Arrow star Stephen Amell was involved in a bit and a fan held a visible sign that read “I can dig that,” with a blow-up image of Diggle’s goofy mug glued to it.

The tounge-in-cheek reference is, mostly, a joke. But it’s also a very real emotion: Arrow fans really dig Diggle, now operating as the superhero Spartan.

But why?

Specifically made for Arrow, with no roots in the expansive DC Comics mythology, Diggle was there from the beginning, from the show’s pilot. Hired by Moira Queen to be Oliver’s bodyguard, Diggle was a retired marine in the private sector while Oliver was fresh from a transformative five years spent surviving on a remote island, plus a year in Hong Kong most fans would rather forget. It shaped Oliver into the vigilante superhero Arrow, but no one in Starling City knew it. So the billionaire prince got a bodyguard. But for fans, it was the start of a beautiful friendship.

One of the constant bright spots for Arrow, even when it falters, is the bond between Diggle and Oliver. They’re brothers in arms, a relationship strengthened by their crusade and nearly torn apart when Oliver walked out between Seasons 3 and 4. That they bond best over their illegal but righteous crusade makes me wonder if that is in any way healthy.

They weren’t always tight, naturally. In Season 1’s “Lone Gunmen,” Diggle becomes mixed up in one of Arrow’s fights and gets poisoned, forcing Oliver to cure him while revealing his identity. But he had Arrow’s back, motivating Oliver to recruit him despite Diggle’s initial refusal to join a murderous vigilante (Arrow wasn’t exactly a superhero this early in his career). But soon enough, Diggle joined Oliver’s crusade for justice, the first to do so.

But Diggle was more than just a useful gun. In Season 1 we saw glimpses of the heart that beats behind his ripped chest. He became close to his (presumably) deceased brother’s widow before ending up with ex-wife Lyla in Season 2. Since Season 3 he’s cared for his daughter — named Sara, in honor of the murdered Black Canary — and has frequently found himself torn between superhero and family man. Diggle has been a comfortable opposite to Oliver, a man with nothing to lose. Diggle is a man with everything at stake.

John Diggle (middle, David Ramsey), as his superhero ego Spartan that he's operated under since Season 4.

And so fans have grown attached to the big guy. Despite his insane pressure in every risky mission, Diggle is funny and is always the voice of reason. His disbelief over The Flash and meta-humans is endearing, and he keeps grumpy Oliver from being a massive dick, like when he reduced Curtis to tears in the Season 4 episode “Beacon of Hope”. Diggle is more than just a good laugh, he ensures they stick together and win the day.

Season 4 hasn’t been good to Arrow. The show has suffered with inconsistent characters and annoying plots, but one of the best things it’s done was quickly resolving Oliver and Diggle’s spat. After Oliver betrayed his team at the end of Season 3 (just a ruse to eliminate Ra’s Al Ghul), Diggle was unable to trust Oliver again. Naturally they resolved their spat and learned to co-operate and even love each other again, but those few episodes when they weren’t together were rough.

The friendship between Diggle and Oliver has been one of the reasons to keep watching Arrow, even when other things make fans think about tuning out. Their brotherly love is thematically fulfilling while also serving as eye candy (they sure do love sparring shirtless). Despite coming from disparate backgrounds and sharing no visible interests, they have each other’s backs like soldiers behind enemy lines.

In the world of superheroes, trust is hard to come by. Loyalty even more so. Captain America: Civil War is more than just a big superhero battle over ideological differences, it’s a personal betrayal felt by Iron Man to his Avengers brethren Captain America. Batman v Superman: Dawn of Justice misstepped in having two icons fight upon first glare, especially since Batman and Superman have one of the most fulfilling, if complicated friendships of all time.

But for the Green Arrow, who has often worked either alone, with a sidekick, or with Black Canary, a brother he can rely on is a rare thing. And he knows it, which is why he’s never letting go of Diggle. Given how much fans have embraced Diggle, I think they dig that.