Shizuma Hoshigaki

is a shinobi of Kirigakure's Hoshigaki clan.

Background
Shizuma was once a teacher at the Kirigakure Academy. During a sparring match between Kagura Karatachi and another student, Kagura quickly went into a frenzy, nearly killing the student. Shizuma stepped in to take the blow, saving the student. While all the others quickly rejected Kagura, viewing him as a monster like his grandfather, the Fourth Mizukage, Shizuma secretly applauded Kagura's bloodthirsty side, insisting that he was as he should be for the coming age. Since then, Shizuma always kept watch over Kagura, protecting him from harm.

Personality
Shizuma is a natural-born combat maniac. Shizuma is well-known for being vicious in battle and having unsavoury conduct during missions. His passion for combat even reaches masochistic-levels, enjoying the pain from being struck by strong opponents and reveling in the memory of it. Loyal to Kirigakure in his own way, he believes strongly that the village has lost its pride since adopting a peaceful nature. As such, Shizuma hungers to restore Kirigakure to the "Bloody Mist" era. A schemer, he gathered a group of followers to aid in his goal bringing back the bloodshed days. He seems to have respect for people who stand up for themselves and possesses an interest in Boruto Uzumaki. He is very manipulative, willing to use people's insecurities and personal dreams to suit his own agenda. He is shown to be very imposing with a low tolerance for failure and will not hesitate to execute his subordinates for their errors as Tsurushi Hachiya and his gang were stiff with fear at admitting to their failed mission. Shizuma also regularly displays an affable, polite side, even insisting on the use of proper honourifics in conversation.

So brutal, Shizuma delights at the prospect of a coming conflict, reflecting a bloodthirsty side reminiscent of his fellow clansman. His hatred at the current peaceful era comes from the view that it has been erasing all mentioning of his clan along with all mentioning of the "Bloody Mist" era to force the change in Kirigakure's nature. His ambitions were shown to even form his own personal Seven Ninja Swordsmen of the Mist. Despite his large ambition and love of the "Bloody Mist" era, ultimately Shizuma is a man with no loyalties at all. Willing to deal with enemy countries, kill allies who fail him, and assassinate innocent bystanders, he is described by Boruto as just a man who looks for any excuse to commit violence, to the point where he wants to start a war simply because he thinks it will be fun. Despite his supposed care for Kagura and the other members of his Swordsmen group, Shizuma shows no hesitation in ruthlessly attempting to kill the former for getting in his way. His savage ambition and stubborn nature also shows him to be impatient and shortsighted, causing him to fail in taking into considering certain risks, like how dangerous Samehada can be or what would happen if he angered the Seventh Hokage by killing Boruto.

Appearance
Shizuma is a deceptively older looking individual despite still being only in his teen years. He is a tall young man with pointed teeth, shoulder-length wavy black hair which he usually lets face all over the right side of his face, and light blue eyes. He wears a red, sleeveless, pinstriped turtleneck shirt along with matching arm-warmers and black pants. He also carries a sword strapped to his waist. Seemingly when emotionally worked up enough, he produces two sets of gill-like features under his eyes and markings around the outer corners of his eyes. After declaring war he dons a sleeveless black jinbaori war coat with tan lining and grey hemming, worn as a surcoat in the traditional style. Across his chest is a long thin scar he got from Kagura after taking a blow that Kagura intended for a student.

While improperly merged with Samehada and the sword's dominance turning him feral, Shizuma grew larger and more defined in his musculature. His right arm also turned grey and fin-like with claws for nails. His face grew out to form a snout with pronounced fangs and wide mouth and his eyes became fish-like.

Abilities
Shizuma is a very capable shinobi, having gained many followers in his goals. Despite being a teenager, Shizuma was tasked with overlooking Academy Student's training, implying a prodigious talent.

Physical Prowess
During his first meeting with Boruto, he showed remarkable speed, able to completely disappear from his target’s gaze and then appear right before them instantly. He also has considerable endurance, barely flinching after Kagura slashed him across his chest and afterward, quickly caught the following sword strike with his bare hand. He has rare talent to perform hand seals with one hand. Able to wield Samehada without rejection, Shizuma is shown to have very powerful and large reserves of chakra. His skill with it can make use of the blade's versatile nature in battle, able to switch between close to long-range attacks, and perform techniques with no hand signs at all.

Kenjutsu
As with many Kiri ninja, Shizuma has excellent skills in kenjutsu, able to effortlessly deflect a barrage of shuriken launched at him. He is also able to use ninjutsu in unison with it to enhance his strike. While wielding Samehada, his most dangerous feat with it is to create a field that will continuously absorb enemy chakra through their open wounds.

Nature Transformation
Shizuma is also highly proficient in Water Release, able to produce two water prisons simultaneously from a distance. Even more, he is able to manipulate them into the air. He can also produce water spikes to attack with or a swirling water stream around his sword, greatly augment its destructive power. He can also cover the area in a thick mist that blocks not only sight inside the barrier, but also sound from all outside the barrier.

School Trip Arc
After performing unnecessary actions in a previous mission, Shizuma was sent to penitence. However, he disregarded that. When Hassaku Onomichi gets into a fight with Boruto, Shizuma breaks it up and tells him to leave the Academy kids alone. Before leaving the scene, he compliments Boruto for having guts to stand up against Hassaku, and tells the students to enjoy their stay in the "Village of the Bloody Mist". Later, he sent a group of delinquents to attack the visiting students. When annoyed by how easily they were defeated, he gave them one last chance to show their worth. After their effort failed and they reported that Kagura would be reporting to the Sixth Mizukage, Shizuma was delighted in this. This was followed swiftly by Shizuma striking down Hachiya for his failure.

Later, when Kagura accepted the test to earn Hiramekarei and began practising with it, Shizuma approached Kagura, reminding him of his bloodstained past and the debt he owed to the latter. Shizuma claimed that the Fifth and Sixth Mizukage were cruel people who assassinated people who opposed their pursuit for "peace". As such, Shizuma said he was beginning a revolution and wanted Kagura as a part of it. When Boruto denied the accusations, he attacked Shizuma, who effortlessly repelled his assault. When momentarily caught off by Boruto's Lightning Release, Shizuma's team, his own personal Seven Ninja Swordsmen of the Mist, appeared to aid him. As Boruto scoffed at the name as there were only six members including Shizuma, Shizuma, however, pointed out that he was including Kagura. Boruto attacked again, only for Shizuma to swiftly defeat him. Ultimately, Kagura accepted Shizuma's words and agreed to join him on the condition that they spare Boruto's life. Shizuma and his team then went to collect the other six weapons of the Seven Ninja Swordsmen of the Mist.

After acquiring Samehada, Shizuma voiced more of his plans, noting that he had allies within the ranks of the Water Daimyō who agree with Shizuma's goal of restoring the "Bloody Mist" era. He also intended to place Kagura as the new Mizukage, continuing the vicious reign of the Fourth Mizukage. Their first act of revolution was to destroy the Kirigakure Memorial Stone. Before they could destroy it, they were confronted by Boruto and Sarada Uchiha, along with Chōjūrō. Shizuma was glad at this development and cut off the area with his Crimson Mist Barrier Technique to begin the battle. As Boruto began fighting Kagura, Shizuma continued to praise Kagura's violent efforts. Suddenly, Mitsuki arrived with proof that Shizuma was conspiring with the Land of Waves for his revolution. It was also revealed that the people Shizuma claimed to have been killed by the Fifth and Sixth Mizukage were in fact killed by Shizuma himself for not backing his plans.

While initially annoyed at his secret being revealed, Shizuma quickly gloated about it, insisting that it would all help to the resurrection of the "Bloody Mist". He also admitted that Kagura was just a pawn in his plan to test the might of Seven Mist Swords, deeming him a waste of the Fourth Mizukage's bloodline. Shizuma then unleashed a veil of red mist through Samehada, giving him a field to absorb his enemies' chakra through their wounds. Mitsuki teamed up with Boruto and the two initially struggled with Shizuma's ability to quickly perform any of his Water Release techniques from any location in the mist, but their diversions and combo assaults were ultimately able to overwhelm him. Samehada began absorbing Shizume, making him go on a feral rampage. Wanting to fix his mistakes, Kagura took up Hiramekarei against his former ally. While too exhausted to defeat the rampaging Shizuma alone, Boruto worked alongside him, each wielding half of Hiramekarei to defeat him and expel Samehada from Shizuma, leaving him unconscious and defeated.

Afterwards, the event was covered by the Mizukage while Shizuma and his gang, minus Kagura, were sent to prison for rehabilitation.

Great Sea Battle of Kirigakure Arc
In the anime, some time later, Shizuma was assisted by Hassaku and Ichirōta in a prison break. Shizuma killed the prison warden and was successful in his escape, while his comrades were recaptured.

Trivia

 * Shizuma's given name literally means, while his surname means.