4) This was one of those things where it makes perfect sense to be but might not to everyone else. the cat girl is the Goobbue Queen, She controls all Goobbues. She killed the Black Hyur's Brother and in some sick, sadistic move wanted to then kill the Black Hyur also. the cat girls hires the woman to kill Levi (hoping that the woman will perish in the process). After the Black Hyur slays Levi she goes searching for the cat girl and when she find her, the cat girl is exposed as the Goobbue Queen and it flashes back showing that the cat girl was present at the death of her brother.
5) the drunk scene was meant to be a sort of I gunna get you drunk so you'll agree to doing something for me scene.
6) the Black Hyur ends up wanting revenge for her brothers death, the cat girl want her and her family dead cause she is evil.

Hope that goes some way to answering your questions and again thank you for your feedback it is much appreciated.