D, Beholder of Death, or Devin, is probably among one of the most hated NPCs in the game. Which is amazing because he has barely two minutes total of dialog which is easily missed if you don't do things a certain way. We know very, very little about him, and hell, some people don't even realize he's an entirely separate character from his brother Darian(D, Hunter of the Dead)! So what can we glean about him from his beyond-minor appearance in the game? A surprising amount!
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I. A Recap
Devin can be found at the Siofra Aqueduct in Nokron, just before the Valiant Gargoyle fight. If you find him before Darian has been killed, he'll be asleep and unresponsive. Once you return to him after Darian's murder, he will be disoriented and awake, and you can hand off the Twinned Set to him. This allows him to be summoned for the Gargoyle fight, and will move him to Deeproot Depths. There, he will show up after the Fortissax fight to deliver a monologue to Godwyn(and Fia's corpse) before disappearing, presumably having killed himself.
II. The Silver Twin
The Twinned Set i a piece of armor made specifically for Devin and Darian rather than standard garb of the Hunters. While I've seen claims that the twins' soul is in some way bound to the armor, this assumption falls apart on closer inspection. There are pragmatic concerns about how such an arrangement worked out for a pair of shunned newborns. But there's also the far more straightforward fact that Devin can wake and speak to us before receiving the armor, so long as Darian is dead. He can also jump up and aggro us without having the armor if we killed Darian in Limgrave.
So it's fairly clear that their soul is linked to their body rather than their armor, and it is their state of consciousness which allows for movement of the soul between their two bodies. Still, the armor is plenty specific to these twins, displaying two intertwined figures which are worn by one body. The armor is symbolic of their inseparable soul, each half representing one of the two twins. The golden one stands taller, carrying its own weight as well as that of the smaller, silver one which clutches it. While the golden half is modeled as fairly straightforward plate armor, the silver half is made to resemble an unarmored body, dressed in flowing robes instead, and thus, the more vulnerable of the two.
Which half is which? A side by side comparison of the twins' skin and hair color may provide some insight.
<-- Darian's skin and hair RGB Devin's skin and hair RGB -->
Darian's is warmer, and just the tiniest bit more saturated. This results in Devin's tones looking cooler and grayer in comparison. Naturally, we can use that as a bit of a reference point to make the claim that Darian is represented by the gold half and Devin by the silver half. This can be supporte further by little tidbits about the characters - Darian is met above ground, beneath the golden light of the Erdtree, while Devin is met in the city of the Nox, who are associated with silver.
But perhaps most interesting are the implications provided by their character traits. As mentioned above, the gold half of the armor exudes strength and stability. It stands on its own two feet and is the main component which the silver half leans on for support. This is reflected in Darian's behavior when compared against Devin's. Darian is stalwart, steady, calm, ready to protect. Devin is, at least in the moment in which we encounter him, more emotionally fragile, broken, delicate, clinging tenaciously to life only long enough to have his revenge against his brother's murderer.
Could this give us any clues about the dynamic between the twins? It's hard to say, given that we don't exactly get to know Devin until after one of, if not the, worst day of his life. Maybe before Darian's death he was just as calm and amicable as Darian. There's reason to think, though, that much like the golden half of the armor, Darian was the one to primarily care for and protect his other half. For one, in spite of being twins, the game makes sure to specify to us that Devin is the younger. This automatically evokes a certain dynamic, the assumption being that the younger sibling may rely on the elder for guidance and protection. Then there is Darian's apparent choice to keep Devin's existence something of a secret, even to a long time traveling companion. Rogier's note tells us that "it seems" Darian has a brother, indicating Devin is someone Rogier hasn't known about until recently. He doesn't even mention him by name in the letter. Darian made a decision to keep Devin a secret, and it could have been to protect him. The protector/protected dynamic is further enhanced by Darian's idle stance which often shows him cradling the head of the silver twin, the bust serving as a reminder of his younger brother who he took it upon himself to care for in a world where no others would.
So where would that leave Devin? It's possible that a pattern of dependence could have emerged, given the nature of their curse. Only one can be awake at a time, and if Darian were to preside over the daytime hours as implied by their 'day/night' duality, this would have left Devin alone in the night. It'd be less likely that he is the one performing necessary daily tasks, as the rest of the world would be asleep at this time. He'd be left to his own devices, and free from obligations typically undertaken during the day which would risk interaction with a populace that was entirely hostile to them. Would Devin have come to see Darian as something of a barrier between himself and this world that hated him?
I've gone over how monumental the acceptance of the Golden Order would've been for this pair of shunned twins in my post on Darian. As a refresher for anyone unaware, what little info we get of the D twins tells us that they were born cursed, sharing a single soul between themselves. As a consequence of this curse, they were rejected by all societies except the Golden Order.
That should make it pretty clear as to why the D twins serve the Golden Order with such fervor. They haven't really got any other option. It's also bound to be pretty world-changing for them to be told that they are worthy of acceptance by the empire founded by the goddess of the world herself. Who could possibly be a higher authority on the matter than that? After a lifetime of shunning and rejection, these two pariahs have finally found a place that will let them call it home.
But nothing in life is free, right? The pair are put to work, or perhaps volunteered themselves. We can't really know, though there would have been a pretty intriguing implication about this if the original 1.0 text had been preserved for the item description of Devin's clothes, which indicates the twins could have been slaves at some point. At any rate, Darian is specified to now be a Hunter of the Dead, while Devin's role is more ambiguous. It's commonly held that he takes on the same job, which is a fair enough assumption. It could also be possible that he is set to scholarly tasks, given that "fundamentalism is scholarship in all but name". This, in some ways may be corroborated by Devin's use of fundamentalist incantations not used by Darian, who primarily uses beast incantations, as well as the fact that Devin is equipped with the Golden Order seal, which demands a higher INT and FAI stat than the Clawmark seal used by Darian.
Regardless of any of that, Devin appears to have been sent on a new mission, something related to but not altogether the same as Darian's weeding of the deathroot. Rogier's letter tells us of Devin's location within Nokron, mentioning, "And it's said he stood before the Prince of Death not far beyond that spot." So Devin has clearly been to the roots of the Erdtree. We know this isn't a place one can just wander into - it's highly sacred, so much so that not even the other demigods slain on the Night of the Black Knives were interred there. It was an honor reserved only for Godwyn. It's a tall order to rationalize a random Tarnished no one like Devin being permitted to go there without invitation, especially not under Morgott's watch. The path through Nokron is wholly inaccessible until Radahn's death, with the Fallen Hawks, who have wandered the city for god knows how long, being unable to find a way out, and Ranni being unable to find a way in. So it's fairly unreasonable to think Devin somehow managed to get into Nokron when no one else could.
This leaves only one alternative path, which is taken via Leyndell, and it is certainly not one Devin chose to take on a hunch or a whim for his own interests.
IV. Plumbing the Depths of the Order
Beneath Leyndell, we can find the Shunning Grounds of the Omen living within the sewers. Traveling deeper still, we can find the Cathedral of the Forsaken, guarded by an illusion of Mohg. Press on past this, and the way is blocked by a seal placed by Morgott himself. So long as he is alive, the seal remains. What's beyond it is a truly terrible sight, hundreds of anguished nomads crammed into catacombs, driven to utter despair in this inhumane prison beneath the earth. And at the farthest depths of this hell lay the altar of the Three Fingers, vassal of the Frenzied Flame and god of chaos, a threat so dire to existence that Melina all but begs us to reconsider multiple times before we even approach it.
It's no walk in the park, that's for sure. But it's also the only other way into the Deeproot Depths prior to Radahn's death, and so it is the one Devin most likely took to reach the Prince of Death.
This also means Devin must have had Morgott's express permission to do so. His seal prevents anyone from reaching the illusory wall which allows one passage into the Depths from the Frenzied Flame Proscription. While I won't claim Morgott is the one to have requested Devin to do this, the fact still remains that Morgott must at least be aware it is happening, otherwise, there's no reasonable explanation for Devin getting to Godwyn in the first place. This further strengthens the claim that Devin was not merely wandering or seeking something of his own accord - he was explicitly sent. And I think this assignment broke him.
Let's take a moment to backtrack to the outskirts of Leyndell, and the Minor Erdtree church. In it, we find 4 items, three of which are explicitly linked to Devin. There's a Golden Centipede, associated with hunters of the dead. There's a Golden Order seal, used by Devin. And there's a gesture, Outer Order, which directly mirrors the gesture received from Devin, Inner Order. We get the Outer Order gesture after listening to spoken echos of Marika, which are as follows:
I declare mine intent, to search the depths of the Golden Order. Through understanding of the proper way, our faith, our grace, is increased. Those blissful early days of blind belief are long past. My comrades; why must ye falter?
How is this relevant to Devin? For one, the twins are associated with the ranks of the Hunters, who Goldmasks laments have strayed from proper scholarly fundamentalism to blindly seeking out an absolute evil to oppose. This illustrates how they have strayed even from Marika's own vision of the Order with her call to examine the tenets of the Order and one's own faith in it.
The word choice also, whether intentional or not, mirrors Devin's own literal searching of the depths of the Golden Order. To reach Godwyn, he descended beneath the Order's capital, going from this noble, golden city bathed in the warm rays of the Erdtree, down through the sewers where cursed children grew up and now eke out a miserable existence, through an internment camp full of suffering exiles, to finally confronting the greatest failure of Marika's Order and the source of the monstrosities which Devin and his brother are assigned to destroy. Marika says, "Those blissful early days of blind belief are long past," and this becomes true for Devin. He has confronted not one, not two, but three layers of deceit and depravity perpetrated by the Order he has agreed to serve. There is no lie to hide behind, no place for faith in the Order to do what is right, no way to any longer deny the imperfections and cruelty of the Golden Order.
And that same Golden Order told you that you were not an abomination. That you were worthy of life, even if the entire rest of the world believes otherwise.
The bliss of that acceptance is now stained with the horrific reality. Devin has reached the depths of the Order, and he has found only misery and abuse, decay and brutality. And at its very center, there lay the once golden and perfect son of that Order, the poster child of all its promises of glory, strength, and goodness, now twisted into the very thing the Order has instructed him is responsible for its ills.
I do not think Devin merely shrugged his shoulders and got over it. In fact, his vicious diatribe against Godwyn makes it pretty clear how deeply this all impacted him. While he has plenty good reason to despise Fia for murdering his brother, Godwyn would have had no involvement in that, and Devin would know. Devin would have seen the lack of response and the lack of awareness in Godwyn as he removed the cursemark from his corpse. So why blame him for anything to do with Darian's death when it's Fia's plot that necessitated it? He's not condemning Godwyn for Darian's death. He's condemning him for sullying the purity of the Golden Order. In his mind, which has been broken by this one-two punch of witnessing the brutality of the Order followed up by Fia's murder of his brother, he's scrambling to hold on to meaning in a world where he is rapidly forced to face his meaninglessness.
So he rages against Godwyn, rages against Fia and her plans to enshrine the undead spawn of this blight on his faith. If he externalizes that rage, he can, for a time, escape his own miseries, and even justify continuing to believe in the virtuousness of the society which gave him and his brother place and meaning, and deemed them worthy of belonging.