Nanami is very wise and reserved. He often appears so calm and indifferent that he comes off as stoic and aloof. He seems like the kind of person who's too serious about his work, but Nanami knows how to separate sentimentalism from service. He's blunt and straight to the point in most conversations and doesn't care for impractical optimism or questions left open to interpretation.
Nanami's stoic personality is in contrast to Satoru.
Additionally, Nanami is very avid and quick to express his irritation, either on his face or verbally with his words. Nanami is often very impatient. He hates working overtime and is very serious about not going a single minute over what's required of him.
Beneath his tough exterior, Nanami is quite sociable and doesn't mind intelligent conversations. He's also practical and overly profound to an almost comedic point on occasion. He claims he only became a jujutsu sorcerer because it's slightly less idiotic than being a salaryman. In the role of one of Yuji's mentors, Nanami is in considerable contrast to Satoru Gojo, who is far more outspoken and easy-going. Yuji and Satoru describe Nanami as gloomy and the former didn't believe they would get along initially.
Nanami is just an average man weighed down by the mundane day-to-day practices of life that stole his youth from him. Nanami doesn't believe age or life-threatening experience propels one into adulthood. Instead, he feels that the build-up of all the little inconveniences throughout life transforms people into adults. He initially treated Yuji as a child because he didn't want to see him abandon his youth for the sake of being a jujutsu sorcerer. However, Yuji eventually proved himself and forced Nanami to acknowledge him.
Nanami knows being a jujutsu sorcerer is a dangerous and demanding job for crazy people, so he has a hard time respecting people in the profession. Even though Nanami and Satoru are longtime friends, the former claims he doesn't respect Satoru despite their mutual trust. He returned to being a sorcerer from the life of a salaryman because he never felt truly appreciated and didn't believe his work had any significant impact on anyone. In contrast, work as a sorcerer allowed him to build up small bits of appreciation from innocent people. For Nanami, this was enough to allow him to live without regrets.
Nanami had a similar yet naturally less mature personality while studying at Jujutsu High. He saw missions as a burden, but his negativity was always offset by his classmate Yu Haibara's extreme optimism. Haibara's death affected Nanami greatly and likely influenced his initial decision to leave life behind as a jujutsu sorcerer. One of the reasons he believes jujutsu sorcerers are trash is because they must force their comrades to accept that they must willingly sacrifice themselves. He recognizes that this leads him to run away from the profession, admitting that it's a more befitting phrase than suggesting he quit. Nanami wants to believe he's never been frustrated by his uselessness, but many of his failures haunt him, such as allowing Haibara to die.
Nanami is a tall, well-built man with blonde hair styled neatly. He has very thin eyebrows and small hazel-colored eyes that are usually covered by his signature sunglasses, which don't have arms that wrap around the ears.
Befitting a former office worker, Nanami is usually fully dressed in a formal business suit. His usual suit consists of a blue dress shirt underneath a tan blazer with matching slacks and light shoes. Attached to his dress shirt, there is a holster that sheaths Nanami's blunt sword.
Nanami's maternal grandfather is Danish.
Nanami is the only sorcerer in his family.
Nanami loves bread and is a foodie.
His hobby is drinking alcohol and cooking for himself.
Favorite food: Bread and dishes fried in garlic oil.
Least favorite food: Ribbon pasta.
Cause of stress: Overtime work.
Nanami represents someone quitting his job as a salaryman.
Nanami does want to get married, but not while he still working as a jujutsu sorcerer.
After leaving work on time, Nanami stays home to eat, drink, and read.
Nanami is the second heaviest drinker in the series, behind Shoko Ieiri.
Nanami first hit the Black Flash four consecutive times during the Night Parade of a Hundred Demons in Kyoto against several grade 1 cursed spirits.
Nanami couldn't blame Geto for becoming a curse user.
Nanami is a model example of what a grade 1 jujutsu sorcerer should be. Yuji and Takuma Ino both look up to Nanami for his demeanor when actively approaching a problematic situation and his incredible skill when it comes down to solving it. Satoru Gojo entrusted Nanami with looking after Yuji due to these traits, and it paid off well for Yuji's growth. Ino, a powerful grade 2 sorcerer, approaches every tough decision with "what would Nanami do" in mind because he believes Nanami always handles things the right way.
Regarding combat ability, Nanami can fight on par with special-grade cursed spirits such as Mahito.
During the Shibuya Incident, Nanami showcased his leadership ability alongside great intellect and fighting strength. Upon learning about Satoru's sealing, Nanami deduced the best move for his team and helped carry out Mechamaru's rescue plan without delay. Understanding that Kiyotaka Ijichi and the managers are crucial for communication in a large-scale mission, Nanami went alone to put protocols for the operation while delegating the other tasks.
After finding Ijichi injured, Nanami quickly tracked down the culprit, Haruta Shigemo, and beat the curse user senselessly without so much as suffering a scratch. This performance, in particular, was stunning to Nobara Kugisaki, a competent grade 3 student. Watching Nanami fight helped her understand that he's on an entirely different level, and that embodies what it means to be a genuine grade 1 jujutsu sorcerer.
Alongside Naobito and Maki Zenin, Nanami was also able to fight the special grade curse Dagon. They were able to overpower him mostly thanks to Naobito's incredible speed, which was backed up by Nanami's support. However, not even the two grade 1 sorcerers could exorcise him.
Master Swordsman: Nanami mainly utilizes a blunt sword in battle with incredible proficiency. Combined with his cursed technique, Nanami can cut through anything, including a blocking opponent, using cursed energy to defend themselves. Nanami wields his blade with grace and balance, striking with extreme speed and precision with every swipe of his sword.
Master Hand-to-Hand Combatant: Besides being adept at armed combat, Nanami is an extremely capable unarmed fighter. His innate technique works with his fists as well as his blunt sword. Nanami used this method to overpower the curse user Haruta Shigemo effortlessly. Each of Nanami's blows were incredibly devastating, a simple backhand was enough to send Shigemo flying across the room. There was never a point in the fight where Nanami was in danger fighting at close range; he delivered one bone-shattering blow after another, and Shigemo would have died without his cursed technique.