HUNTER X HUNTER IS NOT BY ME. ALL RIGHTS GO TO THE CREATOR. OC'S ARE KAZURA, GRANNY CHIYO, KIYIKO-NEE, AND SOME OTHERS.
Kazura grew up in Meteor City for most of her life, and doesn't know her biological family. Her so-called 'family' are Granny Chiyo, from the Zoldyck family, and Kiyiko-nee, a pure-blooded Kurta.
When news of the Hunter Exam reaches her, Granny Chiyo decides to let her go, telling her to look for a boy called Gon, stating he has something to do with Kazura's father.
Kazura decides to take the Hunter Exam, where she meets the energetic Gon, cool-headed Killua, money-obsessed Leorio and the Kurta, Kurapika.
She then discovers her feelings towards Killua, and makes sure Gon is alright. She also watches Kurapika, whilst mentally planning how to get him together with Kiyiko-nee.
And the rest is for you to find out.