Kuro (Sleepy Ash)

If Kuro is not in his cat form, he has shoulder-length, blue hair with his front bangs reaching his eyes. His eye color is red and he has big, dark bags under them. They are always half-lidded and express a feeling of boredom. Just like any other vampire, he has pointed teeth.

Kuro mostly wears a blue jacket which is a tad darker than his hair color with the hood pulled over his head, the black fur looking close to the one of his cat form. He also has a patch on his left shoulder with the Roman numeral 1, probably because he is the oldest of the eight Servamps. He wears the bell Mahiru gave him as their contract symbol around his neck as sometimes seen in official illustrations, which is apart from that mostly hidden under his clothes. His blue jacket is often buttoned open, either a simple black or white shirt hiding under it. On both sides, Kuro has chest pockets. The hem of his jacket splits into many threads, starting short at the front but grow in length as they reach his back. His white pants are skin-tight and held up with a red belt, which is rarely seen. Kuro wears long, black boots that almost reach his knees.

Hundreds of years before, Kuro wears long black hooded jacket with with white pants and darkish grey coloured suit underneath and a long scarf that he let loose.

As a cat, Kuro has black fur and red eyes. Around his neck he is wearing Mahiru's bell as a collar with red leather. His tail splits at its end into four, close to the threads at the back of his jacket in his human form.

Prior to his transformation into a vampire, he had light blonde hair and blue eyes, and his eyes lacked the usual dark bags seen underneath them.

Being the Servamp of Sloth, Kuro spends his time sleeping, lazing around or playing video games. He feels no shame in running away to avoid any trouble and refuses to make decisions, since he doesn't want anything to be his fault, and doesn't want to disappoint anyone. Kuro is a 'shut in' pacifist vampire, and rarely drinks Mahiru's blood, most of the time he refuses and drinks only when he is about to fight. He prefers staying at home rather than going out and seems to dislike the changes of temperature, according to him vampires are delicate to this.

Despite his lazy and at times comical nature (comical due to his laziness and arguments with Mahiru), he is shown to have a dark side. This is shown whenever anyone tries to bring up his past that involves him killing the creator of the Servamps. The mere mention of his past is enough to make Kuro, who is usually nonchalant, to become aggressive. He views himself as a monster, a fact that he strongly detests. As such, he refuses to find out more about his own kind, as it'll only further prove how much of a monster he and his siblings are. He also refuses to turn any humans into vampires to make them his subclass, saying that they probably didn't want to become vampires, and that vampires shouldn't even exist.

Mahiru's straightforwardness and sincerity start to influence Kuro, though he always hides it by feigning disinterest and acting lazy. After Mahiru confronts him in his mind regarding his past actions and assured him he is not alone, Kuro decides to stop running away and face his past, since then he has become more willing to fight and determined to stop Tsubaki. He also prides himself in his cat form, often referring himself as a cute pet or super cute cat and such. He always uses his cuteness to benefit himself, such as to attract the girls in Mahiru's class to give him foods or snacks.

sometimes also tries to use it to calm Mahiru and his friends when he thinks they are worrying or arguing too much, telling them to calm down and be soothed by him, which unfortunately doesn't work for them (except for Licht who is fond of small animals) since they already knows Kuro's characters all too well.

Sleepy Ash is the first and oldest of the eight servamps. When he was a human, he died from an unknown cause, but was then resurrected into a vampire by the creator of the servamp who, at that time, was known as "The Count". His transformation into a vampire horrified Sleepy Ash, as during daytime he could only keep his human form while staying in the shadows while during night time he turned into lion who always seeks human blood. His fear worsened after he destroyed a town where he used to live when he went berserk.

After the destruction of his hometown, Sleepy Ash wandered aimlessly until he heard a rumour about a werewolf. Hoping the werewolf can help him, Sleepy Ash went to the village where the werewolf was last seen. In the forest near the said village, Sleepy Ash encountered the werewolf, Neugear Hartevelt or simply known as Gear, asking for his help to free him from his uncontrollable beast form and thirst for human blood. Gear used an exorcism ritual to separate Sleepy Ash's power and transferred it into a nearby rose. With his power separated from him, Sleepy Ash no longer changed into his beast form during the night. He then requested Gear to throw away the source of his power.

Hundreds of years later, he was approached with the decision to kill a certain person, the creator of the Servamps, by the C3. He called his remaining siblings to a family meeting to discuss whether they should accept the request or not. The discussion became an argument so they decided to do a majority vote, with Sleepy Ash making the final decision. Believing that the experiment that their creator was doing was too dangerous and to prevent more "monsters" like them to be born, Sleepy Ash decided that they should kill their creator and he willingly volunteered to be the one to do it. This decision caused him to have a falling out with his fourth younger brother, Lawless, straining their relationship for years.

Before going to Japan as per request, Sleepy Ash met Gear one last time to inform him of his decision to kill his creator. Upon meeting his creator for the first time after hundreds of years, Sleepy Ash was surprised at the fact that the information was true, having a hard time believing that his creator is indeed still alive. Sleepy Ash's resolve started to waver, but then convinced himself that his creator needs to be killed because his research is too dangerous, which he does. After killing his creator, however, Sleepy Ash began questioning whether he did the right thing or not, and this uncertainty haunted him since then.

Sleepy Ash first met Mahiru when the latter found him lying helplessly on street due to the heat and decided to take him in as a pet, naming him Kuro. Soon, Kuro revealed himself as a vampire to Mahiru. Mahiru accuses him to be the street slasher that he heard recently and will try to drink his blood, but Kuro denies his accusation. Kuro tells him that he will leave once it gets dark so until that Mahiru must not call his name while he is in human form. However, misunderstanding what Kuro meant by his name, Mahiru calls the name he gave to the vampire, forming a temporary contract with him, much to Kuro's dismay. To annul the contract, Kuro must not drink Mahiru's blood until 24 hours passed and they cannot be separated beyond the distance limit or else something will happen, but Kuro was too lazy to explain the detail. Without any choice, Kuro sticks with Mahiru, going shopping with his friends despite his protest that he can't deal with sunlight, to which Mahiru retorts that it's already noon so he should be okay. On their way back, they were suddenly attacked by a vampire named Berkia who is targeting Kuro.

Kuro kicks Berkia away before trying to run away, earning him a scold from Mahiru who tells him to help. Kuro simply replies that he can't stand against Berkia and he is one of people who thinks that someone else will deal with it. However, Kuro immediately changed his mind after watching Mahiru trying his best to save his friends, leading him to protect Mahiru. Kuro fought Berkia and powered up by drinking Mahiru's blood, finalizing the contract between him and Mahiru, making him a servamp. He easily defeated Berkia and intended to kill him, but Mahiru stopped him by reminding him of his own words that whatever happens onward, he (Mahiru) will be the one who make the decision and take the responsibility for it. Relenting, Kuro spared Berkia who revealed that he was ordered by a vampire named Tsubaki who hates him, but Kuro doesn't know anyone with that name.

Tsubaki introduced himself as Kuro's youngest brother and the eighth servamp, the servamp of melancholy. However, Kuro doesn't recognise him as he never met him before and avoids fighting him, opting to run away. Tsubaki proceeds to attack Kuro, and despite the injuries, Kuro refuses to drink Mahiru's blood because he is too tired to fight back after using his strength against Berkia yesterday. They are saved by Servamp of Lust's interference, allowing them to escape.

The next day, Kuro and Mahiru are taken by Misono Alicein, the Eve of Servamp of Lust that saved them before, Snow Lily. They demands Mahiru to give Kuro to them to fight against Tsubaki. While Mahiru objects since Misono and Lily are using force, Kuro quickly surrenders, forcing them to run away. After Mahiru and Kuro protected two of Lily's subclasses, they forms alliance with Misono and Lily. Mahiru and Misono gets into a quick argument regarding their respective servamps, which Kuro unsuccessfully tries to stop by using his cuteness.

Despite this, both Mahiru and Misono quickly bonds due to Mahiru's friendliness, and when Mahiru asks Kuro how normal and important making friends is, Kuro simply says that he will only kill people who Mahiru tell him to kill and protect people who Mahiru tell him to protect, making Mahiru comments that Kuro has no independency.

At school, Mahiru and Kuro overhears some people were talking about Kuro whom they referred with his street name, something that only known by people involves in vampire business. When Mahiru tries to catch up the person, he bumps into his senior Syuhei Tsuyuki who appoints Mahiru to help in summer festival holds by their school town. After school, while Mahiru helps with the festival, Kuro quickly enjoying himself by buying lots of foods from the stalls. While waiting for the fireworks, Mahiru laments how he thought that Syuhei is a vampire but turns out he was wrong, prompting Kuro to comment that being suspicious of people is not like him at all and he is fine with the way he is normally. However, Kuro quickly retracts his words, since Mahiru being suspicious of people will prevent him from doing reckless things. They are approached by a man who asks Mahiru to take the silver case he found to lost and found stall. Mahiru decides to take the silver case to the stall as Kuro warns him that they mustn't get too far away separated.

Not long afterwards, explosions occurred, which originated from the similar silver case that Mahiru was carrying, so Mahiru quickly calls out for Kuro, who drinks his blood and jumps to the sky, throwing the silver case so it will explode without causing any casualties, but Kuro threw it too fast. Kuro assures Mahiru it will be okay since it will usually being blown by wind, but unfortunately, it fell straight down. Before Kuro could catch and throw it again, Tetsu Sendagaya, a person who Mahiru meets a few minutes ago at the festival, caught the bomb into his coffin where it exploded inside.

Tetsu reveals himself to be the Eve of Servamp of Pride, Old Child, who now goes by the name Hugh.

After the incident at Alicein mansion, Kuro and the others are gathering at KTV after Hugh's subclass informs them there's a suspicious person who is strong enough to severely injured a subclass. When Hugh's subclass informs of the person's location, Mahiru and Kuro follows him. The person gives Kuro a dangerous vibe, so Kuro suggests that they should not get involved before noticing a hedgehog inside a cage the person is carrying which Kuro recognised. Mahiru then asks does Kuro has any subclass. Kuro explains he doesn't have one because it's too troublesome since he can't tell if the human still wants to live or not. Hearing Kuro's opinion for the first time, Mahiru tells Kuro that he will always believe in him so he should put more some efforts to be more open up. Kuro looks troubled by this statement while saying that it should be Mahiru who work hard.

The person they are tailing finally face them, already noticing they are following him. He then immobilises and attacks Kuro with his Lead. Kuro notices his wounds are healing very slowly and is about to be attacked again if Mahiru didn't save him. He drinks Mahiru's blood and ties his attacker with his jacket tails, but the person easily frees himself. The hedgehog then interferes, introducing himself as Servamp of Greed, Lawless, while the attacker is his Eve, Licht Jekylland Todoroki. Lawless quickly refuses to ally himself and Licht with Mahiru and Kuro, instead telling Mahiru that if Kuro just make a decision, it can end at once by using a majority vote like they had done before, something that upset Kuro. Lawless continues to mocks Kuro that the latter hasn't change in a bad way, causing hostilities between the two. Lawless then comments that Pride, Lust, and Envy are on Kuro's side, and he doesn't want to get stuck on their side.

Kuro retorts that Wrath and Gluttony are also present at the previous family meeting, to which Lawless simply replies that the two servamps are not so smart but he is sure they haven't forgotten what happened.

Back at the lodging, they sees Licht appearing on TV as a famous pianist overseas, so Mahiru decides to try meet Licht by going to his concert, be he doesn't have any ticket to enter. Light's manager, Crantz Rosen, helps them in by giving a ticket stub. On their way, they spotted Otogiri, prompting them to go to the concert hall to stop the fight before it's too late, only to find Lawless has killed all of Tsubaki's subclasses that were sent to kill him and Licht. Lawless then attacks Mahiru after being annoyed by the latter's insistence they should work together, and Kuro protects him before he could hit the wall.

Lawless then starts to reveal their past when they received a request from C3 to kill a certain someone that they decided with a majority vote, and Kuro was the one who made the final decision. As Lawless is telling this, Kuro starts to unleash his blood thirst. Before Lawless could reveal Kuro's decision, Kuro snaps and fight occurs between the two. They are stopped by Licht who kicks Lawless and immobilized Kuro using Mahiru's Lead. When hearing Licht's piano play, Kuro starts to have vision of his past that makes him depressed and unresponsive for the rest of the day no matter how many times Mahiru calls for him, going as far as indirectly intimidating Mahiru when his eve tried to ask about his past.

Hearing that Lawless has gone missing and deduces that Tsubaki was the one responsible, Mahiru brings Kuro to look for Licht who is weaken due to being too far away from Lawless. Seeing Higan's flame, Kuro tells Mahiru to wait until Tetsu and Hugh came since it's too dangerous with just the two of them, but Mahiru insists that Kuro will be okay and they might be too late if they're waiting.

When Kuro is about to fight Higan, however, black substances suddenly comes out from his body and he is trapped inside a small black ball that also causes Mahiru's Lead to disappear, rending neither of them unable to fight. Fortunately, Kuro is revealed to be all right despite being trapped inside the ball even though he doesn't know what the cause is. In fact, he is seemingly content with staying there since he can't stand with the current situation, something that doesn't sit well with Mahiru who insists that he will find a way to free him. Both Mahiru and Tetsu attempts to free Kuro from the ball by using a saw and a hammer to destroy it, but none of it works and only makes Kuro freaks out and feels uncomfortable due the sounds it made. Mahiru then tries to use a holy water that he got from Crantz, but this also proves ineffective and only made Kuro feels worse since vampire cannot stand holy water. Mahiru decides to bring Kuro to Mikuni, hoping Mikuni knows the way to return Kuro to normal. At Mikuni's antique shop, they are instead welcome by Johannes Mimir Faustus, a researcher and acquaintance of Mikuni who is interested in researching Kuro before Mikuni appears. Since there had been no case like Kuro, Johan and Mikuni sends Mahiru to Kuro's mind, witnessing his memories. It's revealed from his memories that Kuro has been haunted by uncertainty and regret for killing the creator of Servamps. Kuro mumbles to himself, trying to convince himself that he is not wrong and begs for someone to tell him the same. Finally knowing Kuro's problem, Mahiru tells Kuro that he is wrong for averting his eyes from his problem and convinces him to face it instead of running away, assuring Kuro that he will be there for him. Finally found peace, Kuro changes back to normal, determined to never repeat the same mistake again.

Kuro takes the form of a giant black lion and infiltrates the hotel where the other servamps and eves are fighting against Tsubaki's subclasses. Kuro and Mahiru works together and easily defeats the subclasses before going to where Lawless and Licht are who have just defeated Higan. Kuro takes this opportunity to mend his bond with Lawless, thanking him for not forgiving his action as that's what urges him to finally face the Greed servamp. Lawless was taken aback but thanks him back as well, both decides to settle the situation from now on. Mahiru and Kuro then asks for Lawless' current name. Lawless initially embarrassed to tell them, but finally tell them after much insistence by showing a handmade necklace with the name Lawless engraved on it that Licht gave him. Their cheery moment didn't last long as Lilac snatched Lawless' necklace as a revenge against Lawless for killing his friends. To make things worsen, Tsubaki appears beside Lilac, taking Lawless' contract item as he revealed he has defeated Hugh. Kuro attacks Tsubaki who turns out to be an illusion and takes back the necklace, but the real Tsubaki then appears and snatches the necklace once more and destroyed it, causing Lawless to lose his power. As Tsubaki tries to attack Lawless, Kuro protects the latter as he tells Tsubaki that he now has accepted the fact that Tsubaki is indeed a Servamp like him since there's only one person who could created monster like them, which Tsubaki confirms to be the person he calls "Sensei" whom Kuro had killed. Kuro tells Tsubaki that if his goal is to avenge their creator, then he should point his hatred only to him instead of all seven Servamps since he alone was the one who killed their creator. Not wanting to regret anything again, he tells Tsubaki that he has decided to face him so they should be exchanging words and not weapons.

However, Tsubaki dismisses this by saying that the burden of Kuro's regret is too light. Tsubaki then questions why Kuro killed their creator, which Kuro answers it's because his research was too dangerous, however, Tsubaki reveals that C3 are continuing their creator's research. Before Tsubaki can reveal more, three members of C3: Tsurugi, Yumikage, and Jun arrives and quickly corners Tsubaki with their teamwork. Before Yumikage can shoot the cornered Tsubaki, Kuro prevents him, giving Tsubaki a chance to injure Tsurugi and escapes with Lilac with Higan's help. C3 then takes over the situation, taking the Servamps and Eves under their custody and protection, forbidding them to leave their house until further notice.