Hellvy Oberi is a character from the anime Knight's & Magic, where she appears as a senior student and a skilled Knight Runner, the pilot of a magical humanoid weapon known as a Silhouette Knight. Her full name is sometimes listed with variant spellings, including Helvi Oberg or Heruvi Oobaari. As a character, she is depicted as a young adult female with red eyes and shoulder-length blonde hair.

In terms of personality, Hellvy is defined by her competitive and determined nature. She is described as being highly competent in combat and possessing a strong drive to win. Her approach to battle is notably aggressive and fearless, as she is always among the first to advance to the front lines, eager to engage the enemy head-on. This boldness marks her as a natural warrior who does not shy away from danger.

Her primary role in the story is that of an older peer to the protagonist, Ernesti Echevarria, acting as one of his seniors at the knight academy. Hellvy frequently serves as a supporting character in combat scenarios, using her skills to fight alongside the other members of her order. Her key relationships are primarily with her fellow senior students, Edgar C. Blanche and Dietrich Knitz, with whom she is often grouped as a senior trio. Together, they form a unit of capable and experienced pilots who, despite their own talents, are frequently astonished by the prodigious abilities of their younger underclassman.

Regarding her abilities, Hellvy is a very capable knight, noted for having superior piloting skills despite being a woman in a field that appears to be male-dominated. Her combat prowess is demonstrated through the piloting of her personal Silhouette Knight, a high-performance unit named Trandorkis. This machine is a specialized variant of the older Solodreah model, distinguished by its purple color scheme. The Trandorkis is equipped with standard armaments like a long sword, but its notable feature is a pair of magic staffs called Flame Spears, indicating a proficiency in combining melee combat with magical attacks.

Hellvy does not undergo a significant personal character arc of transformation but rather serves as a consistent representation of a skilled and reliable veteran knight. Her development is shown through her growing respect for Eru's revolutionary ideas and her ability to adapt to new tactics and mecha designs. Her unwavering courage and skill make her a dependable ally, and her competitive spirit ensures she is always a formidable presence on the battlefield.