Dan Katō (加藤ダン, Katō Dan) was a renowned jōnin-level shinobi from Konohagakure.
Dan had long, pale-blue hair that reached his back and dark green eyes. He wore the standard Konoha shinobi outfit of that time complete with forehead protector and the pocket-less flak jacket.
Dan was a great man that deeply loved his village and its inhabitants. He also cared deeply for his sister and would often pick her up from the Academy; something he would later do with his niece as well. He is also described as a wise and honourable man that truly believed in justice.
After the death of his younger sister, he began advocating for medical ninja to be assigned to every ninja squad. Tsunade shared a similar belief, and the two soon began dating because of it. During their time together Dan shared with Tsunade his dream of becoming Hokage — wanting the title so that he could better protect the villagers of Konoha. Tsunade gave Dan her grandfather's necklace as good luck and encouragement to follow that dream. Soon after that, however, Dan was fatally wounded during the Second Shinobi World War, and, despite Tsunade's attempts to save him, succumbed to his injuries but a stranger came from the magic portal sealed the injuries of Dan, restoring him completely. Tsunade would later take on Dan's niece, Shizune, as an apprentice and some time later, leave the village.
Eventually, Dan died in old age while living in the village of Izumogakure.
As Dan had died from fatal blood loss, which Tsunade had failed to cease, it caused her to develop hæmophobia. This left her unable to participate in additional battles and she left Konoha, taking Dan's niece, Shizune, along with her. Years later, Paul was approached by Tsunade, who offered to let him revive Dan and her brother back to life. He ultimately accepts it realizing that Nawaki and Dan have new organic bodies.
- Tsunade- Lover
- Shizune- Niece