Joseph

Cartaphilus (カルタフィルス Karutofirusu), also known Joseph (ジョセフ Josefu), is an Alchemist and a monster cursed with immortality. He serves as a recurring antagonist of the series.

Appearance
Cartaphilus has a body of a boy in his early teens, but his body seems to hold something much larger and more sinister. He has no left arm, so he replaces it with others that he has stolen such as Renfred's. He has long straight silver hair with bangs that he uses to cover his eye when Renfred shoots him.

Cartaphilus wears a long coat, shorts, and a striped shirt underneath suit and vest.

Personality
He detests feeling pain and suffering, fearing the day when he will decay. He has no qualms, however inflicting misery on other living things. He lacks motive, and does what he wants with no repressions. He lacks a reasonable motive for his actions and is quick to lose interest. He seems to occasionally have memory loss, wondering who he was talking to just a few minutes after talking to said person, or even going as far as forgetting himself and others, as shown in Chise's dream. He is seemingly prone to (supposedly) extreme suffering, but the reason remains unknown. He hates being called Cartaphilus, saying that it is a cursed name and preferring the name Joseph. Also, for unknown reasons, he has stated that he hates Chise.

History
He is the reason the stagnation by the pond exists. Years ago, he told a man that cats actually had nine lives, by taking them away, he could create a potion that gave their vitality to a human. With it, he could save his wife from illness. By following Cartaphilus, the man killed many cats and the potion he created caused his wife to decay in front of him. Cartaphilus then states that his true intention was to see if a human could resist over the curse of a beast, and the man went mad.

Control Body
Cartaphilus is able to take control over another person's body, as shown when he took control over Stella's body.

Curse of Immortality
Cartaphilus is cursed with eternal life in a body that is constantly degenerating. He requires a constant supply of parts to keep functional.

Quotes
— to himself, about Chise — to Elias
 * "Fufu... are you surprised that I'm a pipsqueak?"
 * "My curse and yours... who knows, they might interact nicely."
 * "You might call me a monster because I do what I want regardless of what that does to others."

Trivia

 * Cartaphilus is the name for an antisemitic legend, meaning "Wandering Jew" in English.