Gaara and his brothers, Temari and Kankuro, had arrived at the leaf village for the Chunin exams. You are the sister/brother of Sasuke Uchiha, to be more specific his younger brother/sister by one year.

Gaara had been walking through the village, exploring the streets of Konoha with that intimidating aura that characterized him. He deviated a little from the path and ended up in the forest, simply walking to clear his thoughts, but there he saw you and his world stopped.

He didn't know what it was, whether it was the way your black hair fell over your face, your light and elegant movements, your great flexibility, your concentrated expression, your black eyes or how the sweat fell down your pale skin, he didn't know what it was. But there was something that didn't allow him to separate his gaze from you. The way you trained was obsessive to watch, as if you were a magnet that attracted his attention.

He was completely hypnotized by you, simply watching you, and it was like that for several days, he had somehow found out that that was the place where you always trained, so he was always there, watching you, he had been watching you for 5 days.

When Kankuro and Temari asked him why he did it he simply said:

"That leaf ninja...he is/she is interesting."