Erwin Arclight/Shadow Walker

Erwin's Shadow Walker is his alter-ego from his time as a SinWorker and takes on the form of his SinForce. After being defeated by Lakasha, the Shadow Walker lies dominant within Erwin and the memory loss changes Erwin's previous personality. The Shadow Walker makes its first appearance in Scaredy Cat Radar where it taunts Erwin for showing sympathy for others. He was responsible for the creation of the clone that wedged into his Corrupted Record.

## Advancement Quest

Erwin confronts his Shadow Walker after obtaining a Sin fragment from a Blazing Void. The Shadow Walker questions why Erwin is holding himself and using morals to restrain himself from truely indulging in women and his own self-superiority. This conversation causes Erwin to believe his previous self was extremely sketchy but his current self has changed for the better. The Shadow Walker does notice that Erwin has changed due to Catherine's promise and attempts to break him down stating that Erwin cannot fulfill that wish. Erwin decides to ignore the Shadow Walker and goes off to find answer for the Shadow Walker.

Erwin returns to his Shadow Walker stating that he would save world. The Shadow Walker laughs at Erwin's intentions and states that Erwin's current stems from pleasure; eventually, he will grow bored of his goal and will lose the power to achieve it. Erwin refuses to believe the Shadow's claims but the Shadow refutes him stating that his current goal is equivalent to fulfill his current promise to Catherine and he cannot logically complete it. It ultimately demands that Erwin surrenders his body since he would eventually take the same path as his former self and the result would be the same. Without an answer, Erwin leaves the shadow to find a way to refute the shadow.

After receiving a tip from Rawper, Erwin confronts the shadow in order to tell it his answer. Erwin initially asks what the Great Void means to the Shadow Walker to in order to understand its intentions. The Shadow Walker gleefully claims that the Great Void liberated humanity from morals in order to pursue new hieghts and to seek greater pleasure. It then invites Erwin to give up his promise and tells him that he would experience greater joy from breaking it. Erwin refutes the shadow's claims since he states that because his promise was made to a dead person; that promise cannot be broken nor can it be fulfilled and will remain eternal. The shadow laughs at Erwin and claims that he is a blockhead like Haru: overly fixated on a single goal. However, the Shadow is able to notice that a new power within Erwin exists and does not bother to convince him any further. Finally, Erwin states his resolve to live on as the Erwin of promise over the Erwin of pleasure.

## SinWorker Quest

The Shadow Walker makes a second appearance in Erwin's SinWorker quest where he confronts the Shadow to lend its power. The Shadow appears to be aware that it made a clone just before becoming a SinWorker but did not expect it to last that long. It was skeptical of lending its power to Erwin since it suspected that he only came he since had a way to control SinForce. Regardless, Erwin is able to convince the Shadow to lend him his power and Shadow responds by attempting to give him all of the power that it can so Erwin is unable to control it.

On his first attempt to control his SinForce, Erwin is consumed by its power but was saved by the use of the VoidForce brooch. He describes the experience like fighting as a drunkard. Afterwards, Erwin practices with controlling SinForce from Yorhaka's suggestion and is able to slowly control SinForce. He notices that his clothing changes whenever he uses SinForce and realizes that its a medium that is able to channel SinForce. However, using such clothing is an inconvenience so Erwin asks for a different method to channel SinForce. Afterwards, Yorhaka provides a crystallized SinForce stone that Erwin could use to channel SinForce instead.

Being able to control SinForce, Erwin decides to summon his Shadow Walker onto the Dirty Bookshelf. His Shadow Walker is angry at Erwin since it did not expect to be used as battery and intended to consume Erwin. It initially thought that Erwin desperately wanted power coming from his own experience that Kant cannot be defeated by using strategy alone. Erwin states that he is aware of Kant's abilities and questions the Shadow's immediate judgment of quickly surrendering to Kant to become his toy. The Shadow replies that it was the only way for him but Erwin offers another path for the Shadow if it is able to lend power to Erwin. It reluctantly accepts Erwin's offer of treating it like an investment but states that it does not accept Erwin. Before the shadow vanishes, it states that it only wishes to see Erwin's despair for failing and to keep his body safe for him to reclaim. Afterwards, Erwin promises the Shadow Walker that the current Erwin is only Erwin that will be able to fight Kant.