Subaru is an extremely tall, fair-skinned, and well-built man, as noted by several characters. His facial features are rougher than most, with thick lips and sharp gray eyes that add to his intimidating presence. He has black hair shaved on the sides, with two lightning bolt patterns etched into each side of his head. The rest of his hair is braided into multiple strands tied back into a ponytail that reaches just above his shoulder blades. He also sports several ear piercings. After the Stagiaire, Subaru’s hair grew longer, with chin-length bangs that frame his face. Though he still keeps his undercut, his remaining hair now flows freely just below his neck instead of being braided.

His standard outfit consists of a large black athletic jacket with chevron designs on a white stripe running along the sleeves. His name is embroidered inside the jacket, a detail implied to be his own handiwork. When cooking, Subaru typically wears a dark chef’s uniform.

In his youth, Subaru was an ordinary boy who longed for his father’s approval, believing that by copying and improving his recipes he could finally earn his praise. However, during a customer showcase, Subaru humiliated his father by baking a cake that surpassed any of his creations. Enraged and ashamed, his father sent him to Tōtsuki Culinary Academy. From that moment on, Subaru’s personality changed drastically, turning cold, calculating, and sadistic.

At first glance, Subaru appears to be an intimidating, punk-like man, largely due to his rough demeanor and striking appearance. On the surface, he seems honorable and composed, even showing civility toward Sōma Yukihira despite the latter’s notoriety. Beneath this façade, however, Subaru takes perverse pleasure in crushing the confidence of his opponents. He specializes in mimicking their cooking styles and mannerisms, spending days or even weeks studying them before provoking a Shokugeki. To further humiliate them, he recreates and improves their signature dishes until his version is undeniably superior. As his ultimate act of dominance, Subaru collects his opponents’ most cherished knives as trophies, going so far as to laugh when taking one that belonged to a late family member. His obsessive precision and analytical mind earned him a 99 match Shokugeki winning streak.

After his defeat at the hands of Sōma, Subaru’s cruel tendencies softened, and he began using his “Perfect Trace” ability in a more positive way, assisting his allies instead of destroying them. His most defining trait remains his obsessive attention to detail, embodied in his personal motto: “Right down to a gnat’s eyebrow.” Subaru studies everything about his opponents, from their cooking techniques to their personal lives, often uncovering details even they are unaware of. His knowledge extends to their habits, histories, and even the patterns of their underwear. To perfect his understanding, Subaru sometimes goes as far as cosplaying as his opponents, fully immersing himself in their identity to replicate them flawlessly.

As a young boy, Subaru grew up in Restaurant Mimasaka, which was managed by his father. Despite his age, he possessed an extraordinary gift, the ability to perfectly replicate his father’s signature cakes by merely observing the recipes or watching the process. Not content with simple imitation, Subaru began improving upon the recipes, believing that doing so would earn his father’s praise. However, his father chastised him, saying that without originality, he could never become a true chef.

One day, during a new dish fair attended by the restaurant’s VIP clientele, Subaru’s improved version of his father’s cake outshined the original, earning higher praise from the guests. Humiliated and enraged by being surpassed by his own son, Subaru’s father expelled him from the restaurant and sent him to Tōtsuki Culinary Academy. The incident deeply scarred Subaru, and his mindset changed drastically. He began his infamous streak of 99 consecutive Shokugeki victories, defeating his opponents by recreating and refining their dishes, just as he once did with his father’s recipe. His unmatched precision and psychological manipulation eventually caught the attention of Etsuya Eizan, who recruited him into his faction and allowed him to pursue his ruthless dueling style freely.

Though it is unclear if Subaru attended the Spring Orientation Ceremony, he was aware of Sōma Yukihira’s bold entrance speech. He survived the grueling Tōtsuki Friendship and Rapport Training Camp, emerging as one of the 628 remaining students and later securing a spot among the 60 participants in the 43rd Annual Tōtsuki Autumn Election. Despite his outstanding record, Subaru became infamous across campus for bizarre rumors, including alleged ties to the yakuza and a fondness for bear wrestling. However, none of these claims were ever proven true.