OVA
Description
Conrad is the second son of the former Demon Queen, Cecilie von Spitzweg, making him the half-brother of both Gwendal and Wolfram. His father was a renowned human swordsman named Dan Hiri Weller, a heritage that defines much of his life. Because of this mixed bloodline, Conrad is classified as a half-Mazoku, which results in his inability to use magic. Despite lacking magical abilities, he has an exceptionally long lifespan, appearing to be in his late twenties despite being over a century old.

His personality is defined by a calm, even-tempered, and seemingly unshakable demeanor. Conrad is highly rational, approaching most situations with a level head and a polite, friendly disposition that makes him appear almost unreadable. However, this placid surface masks a fierce and ruthless warrior. He has a dry and subtly skewed sense of humor, though he is not known for telling good jokes. A key aspect of his character is that he was not always this way. In the past, he was said to have unkind eyes and was more grim, but his perspective changed profoundly after being sent to Earth.

Conrad's primary motivation is the safety and happiness of the Maou, Yuri Shibuya. His devotion to Yuri goes beyond that of a loyal subject or bodyguard. Conrad is Yuri's godfather, a role known as nazukeoya, meaning he is the person who gave Yuri his name. When Yuri's soul was sent to Earth for protection, Conrad was the one assigned to guard it. He met Yuri's parents, and his suggestion that the month of July be called Yuri in his homeland led to the boy's name. Yuri's father made a lasting impression on Conrad, telling him he would not entrust his son to someone with such a grumpy face. From that moment, Conrad made a conscious effort to smile, a habit he maintains to this day, and he treasures Yuri more than life itself.

Within the story, Conrad serves as one of Yuri's primary protectors and most trusted advisors. He is often the first to find Yuri when he arrives in Shin Makoku and the one who teaches him the basics of swordsmanship and even how to dance. His role is often that of a mediator, balancing out the quick temper of his younger brother Wolfram and the stoic seriousness of his older brother Gwendal. He follows Yuri's orders without question, unless they would result in Yuri being harmed.

Conrad's key relationships are deeply interconnected. He is fiercely protective of his brothers, though he expresses it in a far less volatile manner than Wolfram. His bond with Yuri is the emotional core of his character. He also shares a unique and deep bond with Yozak, as they are the only two survivors of the terrible Battle of Lütenburg, a brutal conflict that left Conrad with many scars and a grim understanding of war's horrors. His past also includes a deep connection to Julia, the former fiancée of Adalbert, whose death affected him profoundly.

One of the most significant arcs in Conrad's story involves the loss of his left arm. While protecting Yuri, his arm is severed, and he is believed to have died. He later reappears, having joined the human enemies of Big Cimaron, seeming to have betrayed Shin Makoku. This is eventually revealed to be an elaborate ruse; Conrad only infiltrated the enemy to learn the whereabouts of the four forbidden boxes that could destroy the world. His left arm was one of the keys to these boxes. After retrieving a new arm, he went to great lengths to maintain his cover, even pushing his comrade Yozak from a cliff to prove his loyalty to the enemy king. When ordered to execute Yuri, he instead freed him, immediately returning to his side and stating he would accept any punishment for his actions. He later infiltrated Big Cimaron again, this time openly claiming his heritage as a rightful heir to its throne.

Conrad's most notable ability is his peerless swordsmanship, a skill he developed to compensate for his total inability to use magic. He is widely regarded as the greatest swordsman in all of Shin Makoku, with decades of experience. He is known for his reckless courage when the safety of his loved ones is at stake and is willing to sacrifice everything, including his own body and reputation, for the sake of his king.