One thing is crystal clear: He is not an innocent Shinobi and you may be foolish thinking otherwise. One scene opened the door for this speculation. After Kagura masterfully and brilliantly disarmed Boruto during a friendly kenjutsu battle, Kagura’s face permeated with terror-stricken fear. The scene suggested a hidden past or key element to Kagura the viewer has not been exposed to.
For the past week, a few theories attempted to explain this, including but not limited to believing Kagura was scared of Boruto’s potential (I find this very unlikely) or even due to Kagura’s fear of shedding blood since the village has worked hard to remove itself from its horrid reputation when it was known as the Village of the Bloody Mist.
Well, we may finally have a solid clue. The episode 27 preview for Boruto: Naruto Next Generations explicitly states Kagura has a sinful past. The following is an except of the preview’s description relative to Kagura’s history and upcoming plot: “Kagura recalls events of his past in front Boruto and the others. How does Boruto and his friends feel about Kagura and his unpleasant past sin!?”
Kagura has a sinful past, he works hard to move forward despite not forgiving himself for whatever he did, and others seemingly forgive him such as the Fifth and Sixth Mizukage.
The latest episode 27 of Boruto confirmed the fact that Kagura did something bad in his past.
Another thing which is like REALLY OBVIOUS but revealed officially in the anime was that Kagura is the grandson of 4th Mizukage, Yagura. Like who didn’t guess that out? It was really obvious.
Back to the main topic, Kagura supposedly doesn’t have whole control over his battle senses & body when he wields a sword. He proclaims that because Yagura’s blood runs through him, he loses control and becomes a real shinobi of the Blood Mist Village! He thirsts for blood and undeniably becomes a real monster like the shinobi of the Blood Mist Village were before.
He tells Boruto and others that when he was in the Academy, he suddenly lost control over his body once and recreated the bloody scene the academy exams used to have before. He hurt his friends & classmates and made the whole water floor bloody. This made him so scared to the extent he tried not to wield a sword as then he will lose control and hurt somebody badly. He’s trying to atone for his sin, or more precisely Yagura’s sin.
After having a talk with Boruto and others, Kagura cheers up and realizes that Yagura doesn’t have anything to do with him now and he can control his body on his own will as he’s already trying so hard. The next day Kagura tells the Mizukage that he’s ready to inherit the sword and is ready to give the candidacy test.
And for obvious reasons we know that he will get the sword but the preview for Episode 28 also confirms it as he is wielding the sword and it is explicitly said by his peer that he owns a shinobi sword now.
Is he the successor to Kisame?
Yet again we have more speculation of another newly-introduced character in Boruto, however this is more likely to be true than it is not. In episode 25 of Boruto: Naruto Next Generations, we were exposed to a villainous character named Shizuma Hoshigaki. He somewhat looks like Michael Jackson with razor-sharp teeth. He also has similar gills like kisame had on his face.
In the episode, Iwabe ventures off and Boruto follows him after Sarada reminds Boruto he is the trip leader. A character named Hassaku got into a brief exchange with Boruto and Iwabe, eventually leading to Boruto and Hassaku exchanging blows. From the shadows, Shizuma called Hassaku off; Shizuma proceeded to intimidate Boruto by uncomfortably getting close to him. It reminded me of college freshman trying to hit on a woman at a party but looking like a drunk creeper.
Nonetheless, Shizuma has incredible speed, disappeared before Boruto’s eyes, and appeared directly in front of him. As of now, we do not know much about his abilities, but it is presumed he is a powerful Shinobi in terms of Boruto’s generational level. So, who is Shizuma related to? Most likely the infamous Akatsuki member Kisame Hoshigaki. For starters, they share the last name, both come from the Hidden Mist, and both used kenjutsu. Although Shizuma’s last name has not been mentioned in the anime, according to the below image, Hoshigaki Shizuma (干柿屍澄真) appears in the picture therefore confirming his last name.
One could argue that merely coming from the same clan does not imply Kisame and Shizuma are, for instance, father-son. Once again, the last name Hoshigaki Shizuma (干柿屍澄真) does appear in the image. But, they most likely are related in some aspect. Shizuma also refers to the Hidden Mist Village as Blood Mist Village, implying he believes in the village’s old philosophy of students killing one another in order to pass the academy. Will he be a long-time character like Kisame or die off relatively soon like Zabuza? I guess we will find out!