Von Herder is portrayed as a highly knowledgeable individual with a deep expertise in firearms. He speaks fluently about weaponry and shows a strong interest in solving technical problems and puzzles, highlighting his brilliance as an engineer. Described by Sebastian Moran as a “gun freak,” Herder displays an intense passion for the weapons he designs, often checking on them even during battle and reacting with visible frustration when his prototypes are damaged.

He also shows a playful side, occasionally making light of his blindness, such as joking that the darkness of his laboratory is of no inconvenience to him. However, a bonus comic at the end of Chapter 12 suggests that he may possess some degree of sight; when Moran removes his blindfold, revealing a patterned one underneath, Herder quips, “Ooh… I can see through a simple pattern like this!”

Herder’s enthusiasm for his craft sometimes leads him to ramble about the intricate details of his inventions, regardless of whether his audience can fully understand him. Although generally good-natured, he becomes mildly irritated when others fail to follow his explanations.

Von Herder is a tall man, standing at 6’4″ (193 cm), with light blonde hair and noticeably pale skin compared to other characters. A defining feature of his appearance is the black blindfold he wears at all times, concealing his eyes.

He is usually dressed in a formal blue three-piece suit, consisting of a navy waistcoat, a maroon tie, and a matching jacket. A gold chain is often seen linked to his waistcoat, adding to his refined look. Von Herder also carries a partially mechanized cane with a silver and black design, further distinguishing his appearance.

Von Herder is highly knowledgeable in the field of weaponry, recognized as a leading expert in both the manufacturing of firearms and the specialization of different makers and factories. Beyond his theoretical knowledge, he is a skilled gunsmith and engineer, responsible for crafting custom rifles and equipment for Sebastian Moran and MI6.

As part of his meticulous craftsmanship, Herder regularly checks in with his clients to assess how his previous creations are performing and whether any adjustments are needed. When possible, he prefers to observe his weapons firsthand in combat situations, as demonstrated during the Jack the Ripper incident.

Herder also possesses a sharp analytical ability, often able to deduce the condition and effectiveness of a weapon simply by inspecting it. This attention to detail is evident when he urges Moran to avoid damaging a newly designed silent rifle, emphasizing the importance of collecting post-mission performance data.

Von Herder is inspired by Van Herder, a character referenced in The Adventure of the Empty House by Sir Arthur Conan Doyle, where he is described as the “blind German mechanic” who constructed Sebastian Moran’s air rifle. Additionally, Von Herder draws influence from “Q,” the iconic inventor character featured in the James Bond films and novelizations, known for supplying specialized gadgets and weaponry.