Itachi and Kakashi

Comparison of parameters (during the ANBU period)

Hatake Kakashi: 181 cm tall, 67.5 kg. He was already an adult and experienced ninja in ANBU, earning the nickname "Copy Ninja" even before joining the squad.
Uchiha Itachi: Height 175.2 cm, weight 57.1 kg. These figures correspond to the period of the first part of the manga, when he served in ANBU.

⚔️ Service in ANBU

· Kakashi: Renowned for his unrivaled mastery of missions, he also earned a reputation for putting his mission above his comrades—a principle that changed dramatically after Obito's death.
Itachi: Joined ANBU at age 11 and became a squad captain by age 13. He was a genius who had a Hokage mindset from childhood, but his service was marred by a tragic conflict: as a double agent, he was forced to spy on his own clan as it plotted a coup.

Hatake Kakashi: "The Traitor Son"

Personality: In ANBU, Kakashi is an icy, depressive pragmatist. Due to the deaths of Obito and Rome, he is obsessed with "rules": the mission comes before his comrades. He is cynical, silent, and rarely sleeps, spending his nights at the memorial. Behind his mask of indifference lies a profound sense of guilt and a fear of losing loved ones again.
Traits: His signature technique, Thousand Birds (Raikiri), was developed during this period. In ANBU, he earned the nickname "Cold-Blooded Kakashi" for killing enemies without hesitation, even if they begged for mercy. He wore a mask that concealed not only his face but also his emotions.

🍂 Uchiha Itachi: "Bloody Genius"

Personality: In public, he's the perfect, dispassionate soldier, carrying out orders faster and better than anyone else. Inside, he's a conflicted pacifist forced to become a weapon. He hates war and bloodshed, but he kills in cold blood because he believes it's the only way to save the village. In ANBU, he was wise beyond his years, but utterly alone.
Traits: His main "trait" is the Uchiha clan's curse. Itachi suffered from insomnia and a progressive illness (caused by stress), but hid it. Unlike Kakashi, he wasn't fixated on rules—he rewrote them himself. It was in ANBU that he first woke up and realized that he and Kakashi shared a common bond of guilt over the death of a loved one (Obito for Kakashi, Shisui for Itachi).

They were called the "Shadow Duo." Kakashi saw Itachi as a younger version of himself, and Itachi saw Kakashi as a mirror of his own doom. They rarely discussed personal matters, but they understood each other perfectly on the battlefield without words. Kakashi was the only one who suspected that the Uchiha massacre wasn't just madness, but a necessary sacrifice.