I have a difficult time buying the O-Ren Ishii being part of Bill's gang

She had to survive the only way she knew how. What was she to do? Go to a Christian run orphanage and get educated but little therapy? The pukes who killed her family and their boss taught her that the world was a cold place and that she had be just as cold and ruthless to survive. Could be she had regrets but thats outside the purview of the story.
I think she was lonely even at the top and really had no one to lean on emotionally except that GoGo and her second in command.

You guys are missing part of the psychological angle, these abusers are trying to get the power rush from doing what was done to them when they felt powerless.

I agree with you, but also the other posters too. Also, Bill probably played a hand in raising her up to be that way. He was the snake charmer, after all.

I ALWAYS enjoyed how those in that gang had some sort of warrior's awareness about them everyone else lacked. Oren sensing Beatrix was outside the door listening in, Budd, sensing she was outside his trailer, despite not keeping up with his fight training. He still had that sixth sense. We don't see Oren or Vivica Fox interacting with the rest much in the first movie, but I gotta believe they had similar ties and history, with Bill teaching them, and maybe sending them to that old guy to train. Bill very much molded her into what she is, to a degree.

It's interesting how we see several people Bill trained under, who now help Beatrix find and kill him. Such an interesting world.

This thread is classic 😂

She would have killed her own parents if given chance is what you're inferring towards, hurdling into insinuation category.

I thought this thread was going to be about 'why would a successful mafia boss join some rag-tag murder gang as a sub-servient wage slave'.

I guess your way of tackling this topic is good, too.

Actually, it's not only completely believable, it's actually more likely than that she'd develop some noble moral opposition to killing. Think about the generations of people who went to institutions where hazing the newbies took place. In virtually all of them, those plebes, when they advanced to having seniority in the institution, enthusiastically hazed newcomers themselves. One would naturally think that their suffering would make them reluctant to inflict such suffering on others, but that would be wrong. Their attitude was "I had to deal with it, so do you," or "now I have the power to dish it out." Think of emancipated slaves centuries ago, who themselves became slave owners. Think of Turkish Janissaries of the Ottoman Empire, forcibly taken from their Christian parents and enslaved (it's forbidden in Islam to enslave fellow Muslims), then forcibly converted to Islam (it's fine to convert them after they've been enslaved) and trained to be soldiers, and who then proceeded to be fiercely loyal to the Ottoman Empire, and would go out and attack other Christian enemies and take their children away from them to suffer the same fate.

Human psychology is a strange thing, and very often quite counterintuitive. One would think suffering a trauma would make one reluctant to inflict trauma on others, but very often the exact opposite is the case. Being traumatized makes one feel powerless and vulnerable, and a common psychological mechanism of regaining a sense of power, is to go out and inflict similar trauma on others. It allows you to tell yourself you're not weak after all. In primitive societies, where life is very precarious, you'd think people would value it more, because it's so easily lost; the opposite is nearly always the case, primitive societies can be shockingly violent, and hold life cheap.

No, I am afraid it is quite plausible that O-Ren Ishii would grow up to be a pitiless, remorseless killer herself.

i have a hard time buying that Budd can yield a sword..
let alone be part of that gang