In Tite Kubo's Bleach, many characters endured hard upbringings or personal tragedy, and these moments fundamentally changed them. Among the Soul Reapers, for example, Captain Byakuya Kuchiki was introduced as a cold, law-abiding commander who would sacrifice his adopted sister for the sake of proper protocol, but later, he had a change of heart. That was extremely fortunate, for Rukia's especially.
Rukia Kuchiki went through a few transformative moments of her own, many of them tragic. And what's interesting is that many of these moments could have steered Rukia down a dark path of bitterness, resentment or even villainy, lashing out against a world that saw fit to torment and abuse her nonstop. Rukia had more than a few "ingredients" for becoming a villain. Only the strength of her conviction prevented her from going down that path for real.
Rukia's Origin Is a Typical Villain Backstory
Rukia didn't have an easy life; in fact, her earliest memories involve scraping by on the hard streets of the Rukongai district, stealing food and avoiding the law with her little gang of friends, which included Renji Abarai. Rukia suffered loss before she even knew it; while she was still a baby, her big sister Hisana abandoned her, fleeing into the unknown and marrying Byakuya Kuchiki. She died of an illness just a few years later, and for a time, Byakuya didn't know where to find his late wife's little sister, meaning Rukia was all on her own.
Rukia saw and experienced the worst Soul Society had to offer, and her life was steeped with hardship and injustice from the very start. Many villains start off this way, with Dio Brando of JoJo's Bizarre Adventure fame being a prime example. Dio was angry with a world that saw fit to trample on him, and he sought power at all costs to compensate. Rukia could have ended up like that, as well.
Later, Rukia's fortunes reversed when she was found by Byakuya, adopted into the Kuchiki family and trained as a Soul Reaper. But tragedy struck again when Kaien Shiba, Rukia's good friend, was infested with a modified Hollow, and Rukia was forced to slay Kaien to end his rampage. She was wracked with guilt and doubt, and it would be some time before she finally found peace with what she had done.
If that weren't enough, Rukia faced an unfair execution sentence after she lent Ichigo her Soul Reaper powers and ended up arrested. Her brother Byakuya dragged her back to Soul Society, and she faced jail time and an unusually severe sentence for what she had done. The sheer injustice of it weighed heavily on her and on other sympathetic parties too, and Rukia was resigned to her fate right until the moment when Ichigo rescued her.
Worse yet, Byakuya fiercely defended the unjust sentence right up to the end, seeing his sister as a mere criminal who had violated Soul Society law, and therefore a problem to be eradicated. If not even Rukia's adoptive brother could stand up for her, then what was there left in the Soul Society for her? Central 46, Byakuya, Renji...everyone seemed determined to be rid of her, with justice tossed out the window.
Why should Rukia fight for a Soul Society that treats her like that? Many villains experience a turning point like this, when they determine that playing by society's rules and living up to its expectations will at best gain them nothing, and at worst lead to suffering and tragedy. So, they either shun society and become rogues who viciously defend themselves, or they seek to transform or destroy the world that failed to find a place for them. Rukia had all the ingredients for this transformation, but a few factors diverted her from going down that path, both internal and external ones.
How Rukia Avoided Breaking Bad & Became an Even Better Hero
Internally, Rukia had a strength of spirit that allowed her to endure these hardships without breaking. During her childhood in the Rukongai District, she didn't exactly enjoy the street urchin life, but she was tough and confident, becoming a ringleader among her friends. She didn't seek to harm others; instead, Rukia wanted to provide for her friends, and give them a safe place in her presence. She bore her burdens with grace, and the same was true during the Soul Society arc. At the time, Rukia was horrified by her fate, but all the same, she had the strength to come to terms with it and accept what was happening to her, even if it was totally unjust. Later, she learned to forgive herself for killing Kaien Shiba, and during her battle with Aaroniero Arrurruerie, she recalled Kaien's kind words about the heart, and realized that Kaien never truly died -- he lived on in her.
Externally, Rukia had a little help. Ichigo Kurosaki was her sworn friend and protector, and he stood up for Rukia when no one else would. In fact, Ichigo's quest inspired Byakuya to reevaluate his priorities and relationships, and he made amends with his adopted little sister and swore to protect her and cherish her, no matter what the law said. Byakuya became the big brother Rukia always wanted, and that steered her into a better future, far from the darkness of villainy.
