Imu... Well, first off, I would like to say that Imu is very similar to Yagyu in some way. Second off, I was very close to calling her a meh, but I did some thinking and decided not to. I'll explain as we go on. So, lets start with the backstory.
Well, Imu's backstory is shared with Miyabi. She's Miyabi's childhood friend and they did practically everything together. In some occasions, with Murasaki as well. However, at some point, Imu decided to distance herself from Murasaki due to Murasaki being able to use her root of calamity and not her. At the same time, this caused Murasaki to start being a shut in. Imu witnessed all the terrible things Miyabi witness, such as watching Miyabi's mother die from a youma and watching a youma kill off her comrades. When Miyabi decided to use her blood riot ninja art to kill the youma, Miyabi went out of control, so Imu used the reverse spell to stop, but this caused Miyabi to become mentally disabled to due to the ninja art side effect. Since Imu is very close to Miyabi in terms of friendship, she stayed by Miyabi's side at all times taking care of her no matter what happens. However, due to that, Murasaki felt that Imu replaced her with Miyabi, which then officially made Murasaki a shut in.
Moving onwards to the games, after the battle with Orochi and the destruction of Hebijo, both Miyabi and Imu went to the destroyed castle and saw how destroyed it is. However, due to this, Miyabi's will and determination helped cure Miyabi from her mentally disabled stated as she decided that she'll help restore the pride of Hebijo. Imu, of course, decided to help her. She'll do whatever it takes to help Miyabi gain what she wants. As the story unfolds (particularly in the Hebijo arc) though, when Ryoubi and Ryouna were trying to assassinate Miyabi and Imu, Murasaki was caught it a fire. Imu thought she was dead as she apologized to Murasaki for ignoring her for so long due to her jealousy, but then, due to the rage and sadness of "losing" Murasaki, her root of calamity was finally awakened, but this caused Imu to go out of control and seriously injure both Ryoubi and Ryouna. However, Miyabi got to her and calmed her down by defeating her. After all that, the team moved on with their lives at Hebijo without even thinking about what they did to Hanzo Academy, Gessen, and Homura's group. Imo, that was pretty stupid ending, but this isn't about the arc. This is about Imu. lol
So yeah. In terms of personality, she's very loyal to Miyabi, just like how Yagyu is technically loyal to Hibari. Imu is capable of showing her nice and gentle side to other people than just Miyabi and Murasaki though, which Yagyu doesn't do with her friends that isn't Hibari. This was seen at the end of Yumi's story of Bon Appetit, where her nice side showed after Yumi defeated her and then told her something about how cute Imu is or something along the lines lol.
I find it funny that since Imu is very loyal to Miyabi, she even made a Miyabi fan club of her. This was seen in EV btw in Miyabi's shinobi heart story. Also, whenever Hikage is around Imu, Imu seems to receive some sort of bad luck, which is hilarious. It's also very nice that during SV and her story in Bon Appetit, Imu's relationship with Murasaki is being restored at a nice pace. Such a nice sisterly bond between the two.
So overall, Imu isn't a meh character to me. She's a good character, but she isn't as good as the other characters. It's because of how Imu can show her nice and gentle side to anyone else if she wants to, even if she likes clinging to Miyabi, is the reason why I won't consider her a meh character like Yagyu. I was going to, but it's a good thing I thought things over before making this post.
So yeah, you got lucky, Imu.
Edit: I forgot to mentioned that in Bon Appetit, Imu's relationship with Murasaki is strengthened even further after Imu shared some of the food she made during the tournament to Murasaki and Murasaki gave Imu a gift that represents the sisterly bond and love those two have with one another.
Finally read that one.
Pretty much my thoughts on the character! I really like her, but there is a couple of other girls in front of her. lel
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