In reality, Kanou is a dark and cruel individual who is obsessed with turning humans into ghouls.
In the time following his initial transformation, Takizawa was repeatedly subjected to extensive torture at the hands of Dr. Kanou. This process was intended to force the development of new Rc pathways, strengthened his body and removing any lingering human weaknesses.
Touka Kirishima Mutsuki harbors a grudge for Touka due to his feelings of love towards Sasaki. Takeomi Kuroiwa asks Mutsuki to find Touka as a favor to Yoriko, and gives him a photograph of Yoriko and Touka.
Subsequently, Yoshimura, acting alone in his daughter's place, attacked the 2nd ward for a third time to divert the attention of the CCG and V from his daughter Eto, and was defeated and seriously injured by Kishou Arima.
Ghouls are rated based upon various factors, including their basic strengths, activity levels, influence and hostility towards investigators. In modern-day, there are six rating levels, from SSS (the most powerful) to C (the weakest).
But when kaneki fights arima, his rc cells rise again and his melanin levels drop, and again his hair becomes white.
He threw Mutsuki to the ground, stating he could not explain where they were going, and knocked his captive unconscious. Some time later, the pair arrived at a field of flowers that Torso intended as a surprise. As he smiled at Mutsuki, the other decapitated him with a single strike and later mutilated his body.
The trauma of their deaths caused Kurona to become cold, distant and relatively nihilistic. She decided to become a ghoul because she considered being human and living in the current "twisted world" to be the cause of her misfortunes. Her misanthropy was the result of Akihiro's manipulations, however.
Eren hates Mikasa's supposed lack of free will, and claims he always hated her for having no freedom. It stands to reason that Eren would hate anyone who willingly accepts being a slave to their bloodline without showing the same resolve to break free that he possesses - even someone as close to him as Mikasa.
Eren thanks Zeke for making his plan possible by bringing him into Grisha's memories. When he kissed Historia Reiss's hand four years ago, he saw inside Grisha's memories, and within them, he saw his then future self and the sight of things to come.