On the surface, Michizō Tachihara appears arrogant, impulsive, and prone to solving problems through brute force and his dual guns. His violent temper often leads to conflict with other members of the Port Mafia, particularly Gin, whom he frequently insults and argues with, and Hirotsu, who often curbs Tachihara’s outbursts by threatening him. Despite his rebellious nature, Tachihara ultimately obeys orders, albeit reluctantly, driven by his strong sense of self-preservation.

Tachihara’s pride fuels his temper and thirst for battle, often accompanied by a feral smile during combat. He is quick to resort to violence, showing no hesitation or remorse in eliminating targets, even advocating for murder if he deems someone more trouble than they’re worth. He despises being underestimated or belittled, which often provokes him to act rashly. However, his respect for hierarchy and orders remains intact, as seen when he tries to dissuade Higuchi from defying Ōgai Mori’s instructions, suggesting alternative plans to avoid insubordination.

Despite his rough exterior, Tachihara demonstrates moments of surprising patience and composure. He tolerates lighthearted situations, such as enduring Elise putting bows in his hair or Teruko Ōkura sitting on his shoulders and calling him her “slave.” Even when laughed at by others, he refrains from snapping, showing a level of restraint uncommon in his usual behavior.

Beneath his brash persona lies a cunning and calculated individual, as revealed by his true identity as the fifth Hunting Dog. Unlike his outwardly chaotic nature in the Port Mafia, Tachihara always intended to infiltrate the organization as part of his mission. His cold and blunt confrontation with Yosano Akiko, driven by a grudge for his brother’s death, depicts a far more composed and focused side to his character. His actions as a spy, including his guilt over cutting down Hirotsu and Gin to maintain his cover, highlight his internal conflict between duty and camaraderie.

Tachihara’s inferiority complex stems from growing up in the shadow of his “perfect” older brother, who received praise while Tachihara was dismissed as inferior. These feelings of inadequacy drove him to act out as a delinquent and affiliate with gang activity, yet he could never escape the weight of his insecurities. Desperate to step out of his brother’s shadow, he embraced the opportunity to join the Hunting Dogs and infiltrate the Mafia, using his mission as a way to construct a new identity. However, Tachihara acknowledges that his drive for revenge against Yosano is largely an excuse to reconcile his unresolved negative emotions, illustrating the depth of his internal struggles.

Michizō Tachihara is a slightly imposing young man with short, spiky rust-red hair and amber eyes. A plaster adorns the bridge of his nose, and it is revealed that his natural hair color is black.

Tachihara’s typical outfit consists of a long-sleeved, baggy white V-neck shirt with black borders. The left sleeve is rolled up, rendering it nearly invisible. Over this, he wears a military green crop jacket with beige fur around the collar. Beneath his shirt, he carries a gun strap for his dual guns. He completes the look with dark blue pants, brown boots, and a black band on his left wrist.

When acting as a member of the Hunting Dogs, Tachihara dons the standard Hunting Dogs cape and cap, which he pairs with his usual long-sleeved shirt, pants, and his late brother’s dog tag as a personal keepsake.

Michizō Tachihara grew up resenting comparisons to his older brother, which fueled his decision to stray from expectations and pursue a life of delinquency. This rebellion led him into criminal activities, including one instance where he was caught cracking a safe belonging to a group of criminals. Rather than taking the money he had stolen, the group ordered Tachihara to work for them. Unbeknownst to him, these “criminals” were actually members of the Hunting Dogs. Recognizing his potential, they recruited Tachihara into their ranks, and he has worked with them ever since.

At some point, Tachihara volunteered to become a police operative to infiltrate the Port Mafia. This decision followed the departure of the Mafia’s previous undercover operative, Ango Sakaguchi, from the Special Division for Unusual Powers. As part of his mission, Tachihara successfully embedded himself within the Mafia, using his position to gather intelligence and advance the objectives of the Hunting Dogs.

Michizō Tachihara’s ability, Midwinter Memento (真冬のかたみ, Mafuyu no Katami), grants him ferrokinesis—the ability to manipulate metal. This power allows him to remotely control metal objects, including his Hunting Dogs blade and his guns, which he often uses in combat. His proficiency with Midwinter Memento is so advanced that he can move metal mannequins with human-like precision and make weapons float around him for strategic advantage. According to Teruko Ōkura, Tachihara’s ability is highly versatile and well-suited for espionage, as it can be used for stealing, altering information, and assassination, making him “born to be a spy.”

As a member of the Hunting Dogs, Tachihara underwent rigorous training and experimental enhancement, which granted him greater physical strength and durability compared to an average human or ability user. However, due to his role as a spy, he received a weaker version of the standard Hunting Dogs strengthening surgery, leaving him less capable of withstanding or countering extremely strong attacks, such as the impact from a jet plane.

As a member of the Hunting Dogs, Tachihara underwent light enhancement surgery, which augmented his physical abilities. While his enhancements are less intensive than those of his comrades due to his role as a spy, they still provide him with significant durability. He is capable of withstanding substantial damage with minimal injuries, such as surviving an explosion from an RDG1800.

During his time as a criminal, Tachihara demonstrated skill in cracking safes, a talent that ultimately led to his recruitment by the Hunting Dogs. His proficiency in this area highlights his resourcefulness and technical expertise, making him a valuable asset for operations requiring precision and infiltration.

The name Michizō (道造) is composed of the kanji 道 (michi), meaning “street,” and 造 (zō), meaning “create.” His surname, Tachihara (立原), combines 立 (tachi), meaning “rise,” and 原 (hara), meaning “meadow.”