Toge Inumaki is important too. His special cursed speech ability makes him stand out. Also, the principal of the school, Masamichi Yaga, is likely to be important as he is in a position of authority and has an influence on Gojo and the other students. There could be other characters like the members of different clans that also play roles in the complex web of the story.
In novels, games, or applications, the protagonist or user could create multiple identities or characters to increase their strength, solve problems, or play different roles. Infinite clones appeared in different novels, light novels, and games. For example," Muye's Infinite Doppelgangers "," I Have an Infinite Doppelganger System "," My Infinite Doppelganger in the World of Cultivators ", and " Infinite Doppelganger: I'm Invincible in the Devour Starry Sky " all involved the concept of infinite doppelgangers. In addition, there are some mobile applications that allow users to use multiple accounts or applications on the same device at the same time. In general, infinite clones were a common concept in fictional works and applications, providing more choices and possibilities for the protagonist or user.
It's hard to pinpoint exactly where Gojo is at any given time in the manga. His whereabouts change as the story progresses and different scenarios unfold. It could be in a supernatural realm, a mission site, or interacting with other characters.