Bi Hei has been called buckteeth by others because of his large front teeth.
Bi Hei also has a small goatee.
Be Hei is a nice person, however, he usually doesn't have any courage and he is a coward. He likes to brag and a mythomaniac, lying about something more frequently.
When he was a kid, Bi Hei and his brother Bi Tou found a young Shin and Hyou that were quite famous in the village. Bi Hei started a fight with Shin but both he and his brother were easily defeated by Shin. Shin began calling them the thug brothers from that point forward.
On the way to the battle against Wei for Keiyou, with his brother Bi Tou. They meet up with Shin who came from their same village. He informs Shin about Hyou’s funeral. He tells Shin he should visit his grave after the battle, to which Shin replies he won't until he fulfills their dream, of becoming a Great General. Then he calls Shin an idiot for having such a dream.
When they start forming go’s he explains what they are to Shin. He and his brother then abandon Shin for another squad. They are then kicked out for the Ma Brothers. They then go back to Shin. They then end up in a squad with Taku Kei for a squad leader, along with Shin and Kyou Kai.
The next day he wonders why Shin isn’t nervous at all. When Shin makes the comment that Kyou Kai must have stolen her sword from someone. He asks Shin where he got his extraordinary sword from. He responds by saying Sei, the King of Qin. Then this confirms to him Shin most have stolen it. He and Shin are then shocked by the size of the army.
Later, when Shin is pretending to lead the army, Taku asks Bi Hei what kind of child Shin is like. He tells him an idiot. He then asks Tou why he has been so quiet? He responds that he’s started getting sick when he imagined something. “What the scenery would look like when this many people started to kill each other.” This then frightens Bi Hei.
Later, Taku delivers bad news; the 4th Army has been ordered to head toward Gan Castle. He explains to Shin that their final objective is to siege the Wei City of Keiyou. But first, each army of the militia must rendezvous with the official Qin Army at different castles where they will organize them into proper divisions. He tells them that Gan Castle was the worst possible outcome for them. Because the lord of Gan Castle is none other than lord Koku Gou, a commander renowned as the “Star-Eyed Black Dragon.” A man who truly loves fighting from the bottom of his heart and throw his men into the most brutal battlefields. To survive a battle under his command is like escaping from a deathtrap, which could prove harsher than being at the frontlines. And since he’s just been promoted to general he could be more rash than usual. Which excites Shin, to be fighting under a General.
Later, they find out Gan Castle fell to General Go Kei. So they are to march to Asui, where the 1st and 2nd Army is, and then attack Keiyou with their combined force.
As they get closer to the battlefield mote small fights keep breaking out. Taku informs them that fighting in the army results in severe punishment. They are then mocked by Hai Rou’s squad. And one of his members keeps staring at him very closely. Then they are ordered to get into formation. Shin then pushes them to the front, to see the cavalry unit. Bi Hei comments on how Shin’s mood has changed very quickly after almost getting into a fight with Hai Rou. Later, while information Shin steps out to greet Heki, which shocks everyone.
Then their destination is moved from Asui to Dakan Plains. Five days later, they find out from Heki that the Wei has launched an offensive from Keiyou in an effort to catch them off-guard. In response, the Qin forces have advanced from Asui to Dakan Plains to meet them.
While being split up, he and Tou hope Heki will be their commander, but they are put in the Baku Koshin Unit. While in the very front everyone starts to get very nervous, except for Shin. Taku then informs them most people in the first rank die during the initial clash of the battle, and they must do whatever it takes to survive the first charge. But Bi Tou starts to doubt their chances. Then Taku tells them that he has never lost a single squad member. He tells them to stay within ten steps of each other. If they always stand back to back, they can cover each other’s blind spots. They will attack as five and defend as five. Even against a wounded opponent, they will strike him down together.During the Battle at Dakan Plains, they charge the Wei that used the Rock Formation, but Shin runs to the very front and jumps over the formation killing a great number of Wei and opening a path for the Qin.
Inside the fray, Bi Hei is separated from his squad. He is then hit by a sliced off the head. While he witnesses his first battle he feels completely frightened. But seeing Tou about to killed, he stabs a Wei soldier in the side. Then as that soldier is about to kill him he couldn’t move and was saved by Taku, and then he deals the finishing blow.
Later, they start hearing a rumbling sound. Then a thick dust cloud rolls in, they then see Shin who is trying to tell them something. He then saves them from the Wei chariots. They then see they lost more than half of their men. Taku then tells them that that was only the 1st wave. As the 2nd was about to attack Kyou Kai comes from nowhere with a plan. Her plan was to make ramparts by piling up dead bodies. They then inform the survivors of the plan and they begin to make barricades. When they survive Bi Hou then hugs Kyou Kai.
During the 3rd Ei is killed by a javelin. Shin pulls it out then jumps and kills a chariot driver, knocking it over the whole chariot unit.
When the 2nd wave comes back from the opposite way, Shin comes back riding a horse. Shin then goes to buy then some time to expand the barricades.
As the few survivors are about to get attacked by the Wei infantry, they are saved by the cavalry.
With barely a 100 men left, Baku Koshin tells them they will break through the enemy’s central infantry formation and assault the summit of the hill to slay the Wei General Kyuu Gen. Bi Hei wonders how it's possible for 100 men to break through tens of thousands of soldiers with just a hundred men. Kyou Kai tells them the enemy soldiers will be even faster than normal since they’re advancing downhill. Trying to push against that wave of momentum while running uphill will be unbelievably pushing. In exchange, however, they won’t have to spend as much time fighting through them as usual. And the moment they stop moving, only death awaits them.
They then begin to charge the enemy. When he notices Bi Tou has been stabbed he gets distracted and trips over a corpse. As he is about to be killed he is saved by Kyou Kai.
When they break through the Wei and are right under the summit they have close to 40 men left. Then Taku Unit arrives, with Kyou Ji being carried by Bi Hei and Bi Tou, which makes 46. With their strength almost gone Baku Koshin tells them that he won't cut them slack and anyone who does not reach the summit he will cut down afterward. But those who do will be bestowed the honor of being the greatest contributors to this battle. And be rewarded appropriately, with a reward ten times higher than normal. Then Baku Koshin tells Shin to leave his squad, and join the vanguard, which is low on cavalry. They then encourage him to go. On their way up they are protected by Kyou Kai. When they make it to the summit they are able to hold their ground thanks to general Ou Ki intervening into the battle. Then Shin goes done to join the battle with Duke Hyou. After Duke Hyou kills Go Kei the Wei retreat. Bi Hei begins to cry over all the men they lost, and how they managed to survive. And instead of taking Keiyou City, Duke Hyou has them return home.
He is seen telling stories about the War. Then a child asks him who was stronger Shin or Kyou Kai. Responds by saying that you’d figure it’d be Shin but he’d put his money on Kyou Kai. Because of what he saw“that guy ain’t human.”
He is in high spirits thanks to general Mou Gou decimating the Han. Then the Zhao invade, and he is conscripted to repel them. When they leave the bids farewell to his love Tou Bi. On the march to Bayou, he and Tou meet up with Taku. Then the rest of the new unit starts gathering up. Kou comments saying Shin hasn’t shown up yet. Then everyone begins to worry, He calms them down saying there’s no need to worry. It’s unthinkable for him not to come when everyone else has.
When they begin forming squads, the unit starts to worry, because Shin has yet to arrive. But Den Yuu spots him.
He then informs everyone that this unit will be a special 100-man unit. That does belong to any division and answers directly to general Ou Ki. And they will be sent into the most important clashes, and undertake the hardest fights. In exchange, the rewards will be huge.
As Shin begins to introduce their lieutenant En, everyone wonders who the second is? Except for his old squad members. That night Kyou Kai arrives, to everyone's amazement to be their lieutenant.
When they reach Bayou instead of charging the city they advance right. To avoid fighting on the open field with Zhao cavalry. Instead of charging with the left army, they are assigned by General Ouki personally to flank the Zhao forces while they are engaged in combat with the Qin Left Army and take General Fuu Ki’s head in the midst of the confusion. Ouki then bestows them the unit the name of the Hi Shin Unit. They provide by moving behind the thicket, to loop around the Zhao, to strike them where they least expect.
Then while fighting Fuuki’s elite guard unit, Shin splits the unit in half taking the squads that can still run, fight, and still have energy in them. When Kyo Gai says its 30 vs 300. He tells them not to worry, it might be 300 but there’s only 150 of them between them and Fuuki. 15 deep and 10 across, which makes 150 men. All they need to do is cut down ten ranks of soldiers and they’ll be able to reach the general. Later, Bi Hei tells him that they are already past ten ranks of soldiers. Hai Rou tells him it’s not like the Zhao have been standing around, and their numbers have increased too. When they manage to break through Fuuki decides to pull back his forces to create distance. Bi Hei wonders even though he’s a general and still had 150 soldiers with him, he ran away from just the 30 of them!? Then Fuuki sends out his a cavalry unit to destroy them. Bi Hei tells Shin and Kyou Kai to run since they were mounted they could getaway. But he refuses to leave his men. But they are saved by the Qin Left Army. Then, Bi Tou tells Shin to go and take Fuuki’s head. But Den Ei tells them not to let Shin pull ahead because after coming this far he’ll be the one who gets the general’s head. Shin tells him not to worry. Because his had will be the one to take Fuuki’s head but he’ll split the reward 100 ways, for everyone there, the ones behind, and the ones who died. When Fuuki splits his forces and heads for the bushes Hai Rou notices that they’ll lose him for good. But before he can make it Qin flags come from the bushes. Giving Shin the opportunity to slay Fuu Ki.
A few days later, the Hi Shin Unit was folded into the 4th army to hit the Zhao HQ with their whole army. They then charged the foot of the mountain to set up their HQ. Then they see that the Zhao had practically made it into a fortress.When they enter the Zhao start retreating. Den Ei notices that the Zhao was already long gone by the time they got there. And have moved their HQ and soldiers to a new location. Bi Hei asks Shin if they are going to chase them. Shin tells him, yes, but they had to wait for orders first. While looking the Zhao Bi Hei sees a bush rustling and tells everyone its the Zhao, but it was only a bird. That night they camp in the mountains with the rest of the Army. Bi Hei says he’s going to marry Toubi when he gets back home. Kou asks him if he will be able to? Because it’s not like they’re even going out. He yells to him he will! Kei tells him that Bi Tou is waiting for him to get married first so he can marry Yuu Ri. Bi Hei then tells him he’s sorry, and just to give him a bit longer. Later that night, they are informed that the Zhao has attacked. When they are formed into ranks, a giant man jumps from a hill and starts slaughtering the unit. Bi Hei couldn’t stand, and Tou and Taku tried to help him run. Then, as Houken is about to cut them down, they are saved by Shin. Shin then begins to duel him, then Kyou Kai intervened. He then tells them his name is Hou Ken, the Zhao Army’s Commander-in-Chief. Shin and Kyou Kai pincer Houken. Shin is quickly blown away by Houken. Then he fights Kyou Kai, and they have a fierce duel. Then 500 Zhao arrive under the command of Man Goku. Shin then rises and orders him to fall back and regroup, while Shin and Kyou Kai cover them. Instead, the Kan Ou Army shows up and attacks the Zhao. During the chaos, everyone slowly finds their way back to Shin. Bi Hei notices the tide of the battle seems to be about even. And wonders how they can fight someone like Houken. When Shin wants them to fight Houken, he tells him that he understands his feelings, but he should take a minute to calm down and think it through. And they cannot defeat him by blindly charging like that. If they were to fail in their gambit after entering the middle of that, there’s no doubt their unit will be annihilated. Shin reminds him of when they took Fuuki’s head, and how many of their men gave up their lives so they could take it. And how their center and right armies sacrificed thousands, and what they had to show for it. That is what war is. But right now, the Zhao Commander-in-Chief was right in front of them. But he agrees with him, so he asks if anyone wants to pull out. Bi Hei calls him an idiot, for thinking anyone would run out on him after coming that far. Shin has everyone apart from him and Seki’s squad split into three groups. Take the position surrounding Houken from three directions. Gathering as many of the nearby spears as possible. Then hold position and wait for the signal. On Seki’s whistle signal, all three groups made a beeline for Houken. Then he threw spears at him from all three directions. He deflected all of them, but while he deflected them Shin snuck up on him from behind. He still noticed him, but Shin knew he would and dodged the swing.When he goes to cut him, Shin knew that Houken would still notice and go for another swing so he dodged it and slashed him. But it didn’t work. Before he could make another move he is hit by the backend of his glaive. And before Houken can kill Shin, Kyou Kai protects him and is blown away. Then as he goes to kill Shin, he is protected by the Bi brothers and Taku. Bi Hei takes a gash in his back. Then the unit comes to their aid, Den Ei tells them they are friggin’ amazing, and they did well. Then they retreat. They are then chased down by Man Goku. While De Ei tells Bi Tou to hang on to Shin no matter what, because it doesn’t matter how many of them die, so long as he stays alive the Hi Shin Unit will never die. Everyone from Jouto Village begins to cry, after seeing how Shin is becoming such an amazing guy. Bi Tou then tells them this is just his beginning. Then they are attacked by Man Goku. The Bi brothers manage to get Shin out, while Hai Rou buys them time. Bi Tou’s wound on his back from Houken starts to go numb and his legs won’t move. He tells Tou to go on ahead and sees arrows in his side. Tou then tells him to keep it up just like Shin always does. After losing a lot of blood Hei falls down, but he hears the enemy. He asks Tou if Shin’s heart is still beating? Tou tells him it is. Bi Hei says so’s his heart, and Tou’s. So he has told Tou they should part ways because they’re following their blood trail. So he goes off to the side to act as a decoy, and rips off part of his robe and gives it to Tou to stop his bleeding. He tells Tou they have to keep Shin safe as squad leaders of the Hi Shin Unit and as his friends from Juoto Village. He tells him not to look sad, because once he finished luring them away, he’ll chase right after them and they’ll meet again. And he’s not planning on dying, because Tou Bi’s still waiting for him. And leaves Shin to Bi Tou.
The next morning they find the others after hearing Seki’s whistle. Bi Hei is carried by Chu Tetsu. Bi Hei tells everyone Shin will be fine in Tou’s hands. He tells them to send out search teams, and he has a pretty good idea of what direction they’re in. But Seki tells them Shin has returned, carrying a Bi Tou. As everyone is relieved of their return, Shin tells Hei he’s sorry. And lays a lifeless Bi Tou down. Bi Tou asks Shin why he’s apologizing? And tells Kei and Kou to stop crying. Because there’s nothing to cry about. He completed his task splendidly. Which is why there’s no need for tears. And they should smile and praise him. Then not being able to hold back his tears he says to Tou he did great and screams his name.
Now having lost contact with the other Qin forces, reduced to 13 squad leaders and 36 men the Hi Shin Unit began to revive. They picked up their weapons and began to advance forward without binding their wounds. They find a Qin flag, but it turns out to be a trap set by the Zhao general Ou Ki. After a fierce skirmish Ouki slays Shoumou in one swing.
They then traveled with the Ou Ki Army, when the cavalry and footsoldiers separated due to the mountainous terrain. Shin told Bi Hei and Suu Gen not to overdo it, and general Ou Ki said it was okay for anyone who couldn’t keep up to retire. Bi Hei tells him that he’s not going to sleep after coming this far. Even if he won’t be able to fight he still wants to at least see the end of the battle. Suu Gen agrees.
When they reach the Zhao HQ, they learn that Moubu is under attack by the Zhao, and go to help him. As they are about to fight the Zhao Three Great Heavens’ flag goes up to everyone’s surprise. Then, as the Qin’s morale is almost covered by the Zhao’s Ouki goes and raises the Qin’s. Houken tells them that the right army will be the bait to lure out the Zhao, and he will be the attacker. After Ouki’s lieutenant Tou engages the enemy and exterminates their archers, the infantry charges the Zhao. As the arrows are about to come, they turn left to target the Zhao base camp. Then, Ouki takes to the field and battles Houken. Shin then asks Kyou Kai who does she think is stronger Houken or Ouki? She tells him Hou Ken and gets angered comments from the unit.
As Ouki is about to finish off Hou Ken, he stops, and everyone hears rumbling. They are then surrounded by a huge Zhao army with a Great Heavens flag. The 2000-3000 spectators collapsed in an instant. And the location devolved into a huge melee with cavalry and infantry alike. The Hi Shin Unit then starts blowing through the Zhao. During Ouki's and Houken's duel, Shin notices Gika going to shoot Ouki. As Ouki was about to kill Houken, he is hit by an arrow from Gika shoots an arrow catching Ouki off guard before Shin cuts him in two, and giving Houken the opportunity to stab his glaive into Ouki's chest. His soldiers then drop their weapons in defeat. Then Ouki rises and tells his men to never give up even until death. Then to prove it to his men he swings his glaive at Houken, who easily catches it. Then Ouki starts pushing down cutting Houken's neck. He then explains what a general is. Houken then pulls out his glaive and goes to slay Ouki, but it's blocked by Tou. Shin then hops on Ouki's horse to hold him up. Tou says his unit will act as the distraction, and Ouki's bodyguard team and the Hi Shin Unit will escort Ouki to the left at full speed. Then Moubu and his soldiers use their last reserves to open up a route for them. At Ou Ki's final moments, he tells Shin it is impossible for him to train him. And for a great general like him to personally teach him is to food for a bug like him, to begin with. And matters like those he needs to learn by running between battlegrounds himself. And delve into and overcome strife and carnage together with his men. And bestows him his glaive before dying.
Half a month later, the Ouki Army, which had remained at the front lines out of caution, returned home. He is seen with a crying Tou Bi and looks over at Yuu Ri mourning for Bi Tou.
He was present during the campaign.
He was also present during the subjugation of the area. Dismayed with Shin's errors, he followed the command nonetheless. He was also shocked to see Ka Ryo Ten as their new strategist..
He was present during the invasion, initially marvelled at the sight of Kankoku Pass. Later on, followed Shin to battle against Man Goku Army, relieved when Shin killed Man Goku himself, as his younger brother was avenged. Then, he was present in the night, but not happy with the situation. He was shocked when Ka Ryo Ten accidentally kissed Shin.
He followed Shin and Duke Hyou and also up to Sai, where he admonished Shin for calling Ei Sei, the King, with his name. Then he was also on the Battle of Sai, with Shin as their commander. He tried to stop Shin from duelling with Hou Ken, but was rebuffed.
Bi Hei was seen crying about Kyou Kai's return.
He was also seen talking to Kyo Gai about how Kyou Kai seems much easier to talk to since her return.
He was later seen complaining about how cold it was and how he wanted to go back home.
He was also seen worried when Kyou Kai cut Shin's arm during their sparring match but was soon shocked when Shin flexed it close.
He was also present during the campaign, as part of Shin's main army.
Bi Hei was seen complaining about an arrow stuck to him.
He was later seen celebrating when Shin became a 5000-Man Commander.
He was initially part of Shin's unit, and swapped by Kan Ki as part of the insurance, in exchange of Na Ki. He was nearly killed by the Zhao soldiers when they march to the hills, but saved by Kan Ki Army itself.
Later on, he was with other Kan Ki Army men, looting corpses which he detested, until one of the soldiers handed him over a jade bracelet. Kyou Kai and Shin was enraged upon seeing the brabcelet, nearly ending their friendship. He was later on saved by Na Ki from a beatdown, by killing the soldiers who mauled him. He apologized to Shin later on.
After the battle, he was longing to return home.
He was with the unit, commenting about the brutal training the recruits faces, commenting that he will be disqualified if that training was applied to them.
He was present during the campaign. He was initially seen fighting in Retsubi, then in the Battle of Shukai Plains. He was present during the battle, and lost some of his men due to poisoning. Later on, he witnessed Shin killing Hou Ken by himself.
He was later on promoted to 100-Man Commander, having his own flag and men, but regretted the promotion, throwing a tantrum and saying he prefers to be a 10-man squad leader.