Sieg (Fate/Apocrypha)

Sieg (ジーク, Jīku?) is the main protagonist of Fate/Apocrypha series, who acts as the second Master of Rider of Black during the Great Holy Grail War. He appears in Fate/Grand Order's Apocrypha/Inheritance of Glory event as a Caster-class Servant able to be summoned by Ritsuka Fujimaru.

Appearance
A standard characteristic of Einzbern Homunculi, Sieg's eyes are the same deep, dark red of polished, perfect rubies. His hair is brown, though it appears to darken ever so slightly as he 'ages'. At the outset, Sieg's physique is quite slender and frail, like a newborn infant, and equally as weak. His standard clothing consists of a black waistcoat, white shirt, black slacks, and a pair of black leather penny loafers.

After obtaining the heart of Saber of Black, his physical appearance changes slightly to mimic that of Saber. While his hair only darkens (and shortens) slightly, he grows far taller than he originally was, and the frailty of the past was replaced with a slender-but-hardy build much more suitable for fighting in a Holy Grail War. He also swaps out the loafers for a pair of half-boots.

Personality
''“Perhaps we don't deserve such a thing as free will. I don't really know if what I've done till now is right or not. But, even if there's no rest beyond this... Even if there's only despair beyond this... At the very least I want to walk my own path! We don't ask for salvation either! But I want at least the freedom to choose!”'' —SiegSieg comes into consciousness without anything to form a personality. He is scared of everything but himself, believing to be nothing. He calls himself transparent and colorless because he possesses nothing and had received nothing from his birth.

After escaping and receiving the hero Siegfried's heart, he becomes notably more selfless and brave as he gradually continues to develop as a person. Of his own volition, he decides to forsake a life of happiness, and instead aims to fulfill the desperate wishes of freedom his brother and sister homunculi who would die if nothing was done to save them. Eventually, he even willingly becomes a participant of the Great Holy Grail War in return for their promised freedom and safety as well as for the sake of both Astolfo (who had previously saved him) and Jeanne (who protected him). Due to his young age, he is initially very much naive and clueless about things such as common sense, basic human behavior, and how the world works though he is able to pass as an eccentric but otherwise normal, if slightly clumsy, human with a calm and logical personality in a very short amount of time. While typically very polite and humble, Sieg can at times display a blunt attitude during the rare instances he feels annoyed or frustrated. He also has a tendency to blurt out slightly rude observations without really meaning to which occasionally gets him into trouble with others.

He seems to have a high capacity for forgiveness as shown when goes as far as to unhesitatingly throw himself in harm's way to save both Caules and Fiore when their lives are in peril despite the Yggdimillenia's treatment of his brethren. At the same time, however, Sieg is extremely vengeful when those he cherishes have been harmed before him, not caring whether his enemy is a magus or a Servant, the only thing that matters in his mind is the fact that he will kill them.

After their final encounter with Assassin of Black and witnessing her, along with the children of Scotland Yard's horrific pasts, Sieg's innocent belief of humans being slightly flawed but inherently good creatures crumbles, leading him to began to question humanity's true nature. While he takes Jeanne's advice on not giving up on humans to heart, and ponders over the opinions of several other heroes on the matter, Sieg ultimately seeks his own answer to how he views humans and life as a whole.

Similar to Siegfried, he places little value on his own life and comes to view himself as something that can be used to save and help those around him, causing him to make reckless choices simply for the sake of what he believes 'he should do' instead of what he wants to do. He claims to have no interest in the normal, peaceful life Astolfo spoke of before, but it is revealed during a conversation with Jeanne that deep down, he does have a longing for it but willingly overlooks this fact for what he feels is a more worthwhile purpose that can grant meaning to his life as well as honor to the hero Siegfried who died for Sieg. Thankfully, both Jeanne and Laeticia eventually encourage him to start considering his own value more as he realizes that just worrying about the value of humans and his unfortunate sense of obligation towards others without looking into himself would leave him truly empty in the end no matter what he ends up doing with his life.

While Sieg had his own reasons for opposing Shirou Kotomine's wish for salvation, the main reason Sieg chose to trap himself on the Reverse Side to prevent mankind's extinction that would have resulted from the priest's wish at the end naturally wasn’t solely for humanity’s sake in and of itself. In the first place, Sieg himself admits he hadn't experienced enough to completely believe in humanity though he accepts their nature and simply chose to strive to believe in the good they are capable of. Most of all, it is because he witnessed Jeanne D'Arc's struggles and eventually came to understand her that he acted. For her who had everything taken from her due to betrayal in life, who received the worst treatment conceivably possible for a human, and yet never cursed anyone in the end and even gave up her life to protect their future, Sieg wanted to 'become her strength' and thus carried out her will, acting for the first time on his own personal desire rather just giving himself for someone else's sake because it's what he felt he should do.

When encountered during the Inheritance of Glory event, he's developed even more. His personality is relatively the same as it was at the end of the Great Holy Grail War, but he's notably wiser and tempered by his past experiences. He is still somewhat awkward at interacting with others by himself as seen when he first meets the protagonist and attempts to make himself appear as a solemn dragon, an act he fails comically at as he often has to take many pauses to properly explain the current situation, flounders between the rough 'ore' pronoun and the more dignified 'ware' when referring to himself multiple times in the same conversation, accidentally joyfully roars loud enough to briefly deafen the protagonist when they agree to assist him.