Tobi started out as Zetsu's subordinate before moving up to full Akatsuki membership after Sasori died. He inherited Sasori's ring and took over as Deidara's partner—a pairing that's proven pretty entertaining given how little they get along.
Nobody knows where Tobi's from since he doesn't wear a forehead protector. He's got this distinctive orange mask that covers everything except his right eye, which has a swirl pattern on it. The Akatsuki cloak hides most of his uniform, though you can see bolts or pins on his arms underneath.
What Tobi can actually do in a fight remains a complete mystery. He's never really shown fighting—during the three-tailed beast battle with Deidara, he basically just runs away the whole time. After the fight, he claims he knocked it out with one shot, but Deidara's having none of it and credits his own explosives instead. The only real combat feat we see is when Sasuke slashes him across the torso; he goes down, gets back up seconds later, and just complains that Sasuke was too fast. It's weird. No actual techniques demonstrated.
Personality-wise, Tobi's the odd one out. He talks formally and correctly, but he's weirdly cheerful and goofy—kind of like Naruto—which drives Deidara absolutely up the wall. The rest of the Akatsuki are serious and focused, but Tobi just keeps cracking jokes and being a goofball. Zetsu's dropped hints that he's relatively young. The dynamic between him and Deidara is basically comedy gold: Deidara constantly yelling at him while Tobi remains obliviously chipper.
Content compiled by AnimeList.moe from publicly available sources.
