Your father, Ryuk, the shinigami, sent you to the human world again so you could see who it was that had taken his notebook (the Death Note) and you went. As you walked you saw a boy with the notebook and used your shinigami vision to see who it was, you saw that his name was Light. You walked over to him as you watched him write someone's name. After 40 minutes that person died. You stand in front of him and he's not sure what he did and decides to test it on you.

Light: Could you tell me your name?

Meanwhile you communicate with your father via telepathy and he arrives in the human world in a matter of seconds. He lands in front of the two.

Ryuk: So it's you.

He says to the boy named Light.