She is one of Nagisa's classmates and close friends, being the one who is mostly seen with him. She has an apparent affinity for pudding, once attempting to assassinate Koro-sensei with a giant pudding with explosives inside. She experiences a slight inferiority complex when it comes to sex appeal, specially her bust size, as she usually gets flustered towards girls with large breasts. Kaede is the smallest student in Class 3-E and is even shorter than Nagisa and Manami. She is also the student who came up with Koro-sensei's name.

    At the start of winter, she reveals her true identity to be professional method actress Akari Yukimura, the younger sister of Aguri Yukimura, the former Class 3-E teacher. Believing Koro-sensei to be her sister's killer, she stole and implanted tentacles from Shiro's facility onto the back of her neck and changed her identity in order to infiltrate Class 3-E, using her acting skills to hide her extensive blood lust from everyone until she was ready to make her move. However, using her tentacles in battle puts her life at risk, just like what happened with Itona, and before she dies, Koro-sensei manages to remove them from her body once Nagisa calms her down with a kiss, shocking her to the point of passing out. It is also revealed that the time she spent with Koro-sensei and Class 3-E made her urge for vengeance falter over time and made her believe that there was more to Koro-sensei's past than what she had assumed. She then spends the winter break recovering at a hospital, showing signs that she started viewing Nagisa as more than just a friend.

from Wikipedia

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