Daijirō Ōhara commands the Kameari Kouen-Mae Police Box as its Section Chief, overseeing officers like the unruly Kankichi Ryotsu. He cuts a distinctive figure: short and stocky, framed by thick eyebrows and a precisely square mustache. His attire is consistently the full police uniform—blue pants, long-sleeved coat, police hat, black tie, and black shoes—complemented by a brown satchel. A practical buzzcut hides beneath his hat. Professionally stern and serious, Ōhara fiercely guards the police box's order and reputation. This often ignites his short temper, particularly toward Ryotsu's laziness or schemes, prompting his trademark outburst: "Baka mon!" ("You idiot!"). Yet beneath this strictness lies a modest, diligent, and considerate man who strives to maintain dignity before superiors like the Chief of Police. Deeply rooted in tradition, he practices kendo, judo, shogi, calligraphy, bonsai, and savors local cuisine and ancient theater. Modern technology flusters him, sometimes leading to accidental destruction of gadgets via remote control confusion. He commutes via bus and train. Ōhara's dynamic with Ryotsu forms the bedrock of his work life. Decades ago, he arrested a drunken, civilian Ryotsu for causing trouble—an encounter that reportedly spurred Ryotsu to join the force. Though perpetually exasperated by Ryotsu's disobedience, Ōhara holds a paternal regard for him, occasionally showing empathy or pride during rare moments of diligence. He even gifted Ryotsu the sandals he still wears, replacing uncomfortable regulation shoes early in Ryotsu's career. At home, Ōhara finds stability with his wife, Yoshiko, who offers crucial advice during stress. He shares a warm bond with his daughter, Hiromi, having taught her Chadou (tea ceremony) and proudly showcasing her skill to subordinates. His protectiveness initially fueled intense resistance to her marriage, though he ultimately accepted it, becoming a grandfather to her two children. Among colleagues, Ōhara values dependable officers like Keiichi Nakagawa and Reiko Akimoto, addressing the latter with the affectionate "-kun" suffix. He maintains a generally positive rapport with his superior, Gomesu Tonda, collaborating to contain fallout from Ryotsu's antics. Occasionally, Ōhara reveals romantic interest in coworkers like Haya Isowashi, bonding over shared passions like shogi. His current stricter management style contrasts with his experience under the gentler superior Iwata. Notable trivia includes inconsistent manga birthdates, though one anime episode identifies his zodiac as Aries. A rare, whimsical side emerged when he unpromptedly donned a schoolgirl uniform after visualizing himself cross-dressing, showcasing unexpected flexibility within his traditional persona.