The Abandoned Sister

One night, a hooded fourteen year old boy was carrying a crying baby girl. Hurriedly he knocked on a door and then left the baby on the ground. He ran away into the dark night.
****************
Rin Tahida, an infamous killer heard someone knock on her door. Rin walked cautiously wondering who was knocking on her door at night. She opened the door and saw a crying baby girl on the dirty ground. A motherly instinct kicked in and she picked her up, cooing at the baby. Rin named the baby, Hisako (means long-lived child according to my info source) Tahida. She decides that night to keep and raise her as her own. Rin trained Hisako to become a killer like her. When Hisako's "mother" was taken away, she is left homeless. When she finds out about the Hunter Exam, she decides to take it. There, she finds out about her true identity.
::::::::::::::::::::::::::::::::::
This is going to be a hxh fanfic, btw I made up Rin Tahida, I
don't claim anything. ik, sucky prologue.