Yukimi is a member of the Iburi clan, a group whose smoke-transformation ability is too unstable in its natural state to let them survive on the surface. She and her brother Tenzō grew up underground with the rest of their clan, though they'd sneak up to ground level whenever they could just to listen to the world above. Everything changed when Orochimaru found them. Recognizing the potential in their powers, he offered them a deal—he branded each clan member with his cursed seal, which stabilized their transformations enough to make them viable.
Yukimi's defining trait is her relentless optimism. She's almost always smiling, fiercely devoted to her family, and stubborn about it in the way only a kid can be. When the rest of her clan gave up hope that Tenzō was alive, she refused to accept it. That loyalty cuts both ways though—losing someone hits her hard, and she's not great at hiding it.
She's a short, fair-skinned girl with long curly brown hair, blue eyes, and freckles. Like everyone in her clan, she wears simple rags and bears Orochimaru's cursed seal on the back of her neck.
As for her abilities, Yukimi can transform into smoke while staying solid enough to interact with the physical world. In that form, she can possess people—essentially slipping into their body like a second skin and controlling them from the inside.
Content compiled by AnimeList.moe from publicly available sources.