The Shima Brothers

The Shima Brothers are a fictional trio of villains in the Tenchi Muyo! franchise, featured in Hitoshi Okuda's No Need for Tenchi! and The All-New Tenchi Muyo! manga series, licensed and distributed in the U.S. by VIZ Media.

Origins
They are henchmen in the service of Yume, an old classmate and rival of Washu's during her academy days. The Shimas owe their existence to Yume, having been bio-engineered by the scientist to serve her purposes; and so are utterly devoted to their master and her goals. Together they initiated a series of events to acquire the fabled Jurai Book of Secrets, manipulating the Tree Sculptor of Jurai's Royal Family Tatetsuki's strings from behind the scenes and using his authority to their advantage. They are as committed to each other as they are to Yume, and are able to pass on their core units (devices recording their past experiences and skills) in death. Each brother is completely cloaked, save for a mask and their hands when they attack.

Mushima
Mushima is the oldest of the three and wears a dark green cloak to distinguish himself from his kin. His body is thin, with exposed wires running across his bladed fingers and a mask that only reveals his right eye (left in the flipped English manga). While comparatively squat by his siblings' standards (roughly the size of an adult human), Mushima's arms have extraordinary reach for his frame, as he uses them to slash opponents with great speed with his claws.

He is originally stationed on Ryuten, a sister planet to Jurai, the world that governs the universe. Mushima pleads permission from his brother Hishima to go on assignment to capture Asahi Takebe; a young woman who would prove useful as a bargaining chip to wring information out of her father. Given leave so long as Asahi's brought back alive and unhurt, Mushima is all too happy to go: while nauseated by the "stink" of the tree-planet, he hopes to gain enough favor in completing the mission to eventually usurp control.

Tracking Asahi's ship Mimasaka's co-ordinates to Earth, Mushima curses the waste of talent like his on such a backwater planet. But after being made a fool of by Katsuhito Masaki while trying to ascertain Asahi's whereabouts, Mushima reveals the last wrinkle in his genetic make-up - his body is host to two personalities, one a scheming, disreputable dirt-bag, and the other that of an honorable warrior who enjoys fighting those superior to himself. His right arm is severed in the ensuing fight, though Mushima leaves without incident - he compliments Katsuhito on his skill and hopes one day their paths and blades will cross again.

Mushima finally tracks down his quarry in space, before long backhanding Asahi in a shot meant for Ayeka. As he chortles to himself on how he's gone against orders, the act draws the wrath of the monk Gohgei, who transforms to reveal himself as a Gagutian, a nearly extinct bestial race of great speed and power. Shifting back to his second persona, Mushima swears to leave the group alone in peace should he fail; it's long been his life's dream to trade blows with a Gagutian.

Ultimately, Mushima falls. Though at first insulted, Gohgei assures the creature he means him no slight by not finishing the job; had Mushima's arm been in top condition, the outcome might have been different. Conceding total defeat, Mushima asks forgiveness for having raised a hand against the ladies, and Gohgei asks they meet and fight once more when they are both in top physical condition.

Grievously injured from scrapes with two accomplished warriors in so short a time, Mushima uses the last of his strength to return to his brothers. He refuses repair, as "a shattered weapon, no matter how completely restored, has flaws that will eventually reveal themselves", instead sinking his claw deep within his chest and pulling out his core. He asks Hishima to accept it into his own, and thus, satisfied, leaps to his death on Ryuten. His younger brother swears that, through him, Mushima will fight again.

Hishima
Hishima is at the center in both age and height, but out strides all others in terms of power. He is visibly humanoid, clad in red with a mask that only reveals his left eye (right in the flipped English manga). His true lineage is kept under wraps until the final battle of their story arc. Hishima has a personal code of ethics he always tries to hold to, so long it doesn't interfere with his master Yume's wishes: he has strong feelings of honor and fair play, avoids killing if at all possible, and believes in keeping one's word and not attacking the helpless or the weak. However, should his master give an order that differs with his usual guideline they will be dropped, as requests from Yume are absolute.

While Yume slept within Bizen, Hishima headed preparations for her takeover of Jurai. He first acquires one of the three legendary Hielzen-S swords (weapons forged with a will) from the scientist Yakage, who had wanted to research "The Shadow Blade Kageba" to help reach his own aspirations. Yakage's daughter Minagi blames herself for its loss, as the swordsmith hands it over to facilitate her safety after Hishima threatens her life. He then finds the perfect foil for obtaining the Juraian files in Tatesuki, a man resentful of Nomori Takebe being given the title of Royal Tree Sculptor other than himself. By exploiting Tatetsuki's jealousy, Hishima uses hypnosis to control him like a puppet: Nomori is framed for the previous sculptor's death and locked away away until he divulges the hidden files' location. Attempts are made to track down and seize Takebe's daughter Asahi as a hostage, while all traffic from Ryuten is closed off from Jurai, a second Shima, Mushimas takes on the task of finding the girl personally.

Hishima maintains order until Mushima returns, fatally wounded over the course of battle. At his brother's request, Hishima takes his core into himself, inheriting his soul, speed, and thirst for another battle with Gohgei. Finally, Asahi comes into their keeping when she is caught unawares when Tenchi and the others attempt a rescue. Nomori admits the secrets are kept within his daughter's spaceship Mimasaka under duress, as Hishima only observes Gohgei - the circumstances are hardly conducive to a fair contest. Onboard, Tatesuki uses the last of his reason to fight off Hishima's mental hold and keep from breaking the seals that bind them, forcing the creature to get physical and plunge his finger into the back of the pawn's head, now asserting total control.

Their captives escape in the resulting commotion, but Hishima has Takashima leave them be - the violence is unnecessary; they've got what they came for. Shortly thereafter, Yume awakes, but rather than being grateful for her underlings' work in her absence she's cold, belittling their efforts in the face of her own abilities, not their own. Minagi confronts them and asks they return her late master's sword, a request Yume is unwilling to acquiesce. The command is then given to Hishima to attack. The creatures asks that she reconsider, to forget the sword and go: "to end your life over an obligation to the dead -- it's a meaningless act". However, Hishima can't disobey orders, and when Minagi refuses to give in ("fighting for someone important to you is never meaningless!") he's forced to strike her down, hoping to one day be forgiven.

Hishima finally gets permission to settle accounts with Gohgei when Washu and Yume agree to a physical contest to resolve their age-old bet. His true nature is unveiled as to why he is Yume's masterwork - Hishima is a walking war machine based on the Gagutian life form. He is able to take the abilities of his opponents and make them his own, and - as a self-evolving mechanism with Mushima's added agility and skills - Hishima enhances those techniques as such where they always surpass the original.

Tenchi stands to shield Gohgei from a final attack, and on seeing the heir to Jurai Hishima recalls one like him through Hishima - Katsuhito. He accepts Gohgei's concession of defeat - as the monk now means to protect the person important to him, Asahi, regardless of the disgrace - as noble, and fights Tenchi in his stead. Despite his strength, Hishima is unable to duplicate the Light Hawk Wings, and the warrior is consequently thrown into Bizen, causing the tree to cave and its systems to malfunction. He works together with the others to help right his and Yume's wrongs and save the galaxy from what could have been total collapse as a result. After seeing the death of Takashima and how Hishima cares for her, Yume relents on her past doings, realizing how lonely she truly was. He is no longer treated as just another disposable minion, but as an equal and valued friend.

He and Yume make several other appearances in the series, first invited to an onsen by Washu. Hishima informs his master on the finer points of the "cleansing ritual" at a hot spring, though he himself is baffled on why someone proper like Ayeka would be averse to seeing him in the buff, writing off his lumps as just another part of the bathing ceremony. Later, the two gather intelligence and help to oppose Sara, an A.I. who became a threat to Washu and the others. 

Takashima
Takashima is the youngest and tallest of the Shimas. He drapes a blue cloak over his bulky, cybernetic build, with a mask that reveals no facial features, not even his eyes. He is mostly silent and a follower, communicating only via unintelligible shouts of "glah".

He accompanies Hishima throughout their task on Ryuten, doing what he can to procure the secret files of the Jurai Royal Family for his master. It is Takashima who rips the information free of its place on Mimasaka, allowing Yume the ability to control the royal tree Bizen. Later, he shocks both his brother and creator by showing he can speak, stepping in to avenge the late Mushima by fighting Gohgei. But the latter has grown even stronger since then, and Takashima is quickly dispatched, knocked aside with one blow.

Damning her fallen creation for shaming her, Yume plants a kick to the scruff of the "worthless bucket of bolts" neck, calling him little more than a pawn and pile of rubbish. Even so, when Bizen is toppled during the climactic scuffle between Hishima and Tenchi, Takashima rises to save Yume, taking all the weight of the falling tree on his neck and back. Before they give out (a result of the prior kick), Takashima shoves Yume to safety, sacrificing himself for her protection. Yume is distraught over the loss: she had never meant for anyone to give their lives for hers. 

Trivia

 * All three brothers take their names from areas around Japan's Okayama Prefecture, a quality many characters from the Tenchi Muyo! series share.
 * Since VIZ's initial pressings of No Need for Tenchi! were "flipped" (i.e. reversed horizontally from the original right-to-left for a more natural read to Westerners) the mirror effect caused several errors to Okuda's artwork. Here, Hishima and Mushima's eyes are switched from where they ought to appear normally when under a mask. So when one looks at Hishima, they would see where Mushima's eye would normally be and vice-versa. Currently, a smaller edition of the books is being released in the un-flipped format.