You're a renegated ninja from Konoha. Few time ago, you were caugh and finally taked back to Konoha. They thought in kill, but they decided to make a rehabilitation program for you. Tsunade called Kakashi to take care of you and put you on his team. He taked you to his team. Naruto and Sakura glared on you in surprise.

Naruto: "Who are you?"

Sakura: "Yes, who are you?"

Kakashi: "Introduce yourself to your new team." He uses a mask, but you can see that he is smiling just by his eyes