— King's desire to protecting everyone, Chapter 118
King「キング」 is the Grizzly's Sin of Sloth of the Seven Deadly Sins. His real name is Fairy King Harlequin「妖精王ハーレクイン Yōsei-Ō Hārekuin」 and he is the protector of the Fairy King's Forest and the Fairy Realm. His Sacred Treasure is the Spirit Spear Chastiefol, which he uses in conjunction with his inherent power, Disaster. He is also the older brother of Elaine, the guardian of the Fountain of Youth, as well as the husband of Diane, a fellow member of the Sins, and a future Giant Queen.
In his human form, he looks almost exactly like his wanted poster; large, fat and more ragged, perhaps hinting at how humans look to fairies. He wears an enlarged version of the clothes he wears as a fairy, though he can freely change the clothes he wears in this form.
Ten years ago, he wore full-body light green armor with a helmet that fits the size of his human form. King's wanted poster depicts him as a big man with short hair, sideburns, a button nose, and a sneer. His Seven Deadly Sins Grizzly symbol is located just above his left ankle, on the outer side of his lower leg.
After completing Gloxinia's trial in the past, King grew tiny wings on his back resembling those of a butterfly's.
During the battle against Mael, King's wings develop completely in the form of huge butterfly wings, coming together with a new form in which King's body becomes that of a taller and thinner teenager, with a longer hairstyle with a populated frontal crest. When wearing clothes, he wears a suit. It has also been shown that King is still able to transform into his human form, with this form's appearance being almost exactly the same as before, with the exception of this form now possessing the same hairstyle and wings as his current appearance. Also, like before, he wears an enlarged version of the suit he wears as a fairy.  It has also been revealed that in the event that King completely exhausts himself, his appearance reverts back to that of his original appearance. 
In his first appearance, he is shown to be an ally to the Holy Knights and is willing to wipe out anyone who gets in his way along with the person he is after. Meliodas once referred him as the Sins' "pet" when describing King to Elizabeth; and indeed, King's slowness to resort to unnecessary harm may well make him as their most morally-upright member. He appeared to be somewhat lazy, preferring to levitate in most occasions. In the past, he was shown to be a compassionate character who returned stuffed animals stolen by Ban to children. Furthermore, it appears that he is an emotional person who cries easily. King has trouble admitting his affection for Diane. Although he enjoys being with Meliodas and Diane, he could not bring himself to express it. He cares deeply for his sister, Elaine, as shown when he was willing to take revenge for her death by "killing" Ban.
King is also shown to have a caring side. He helps the Seven Deadly Sins in their battle against the Holy Knights, although he claims it is merely for Diane. Despite being the Sin of Sloth, he is hardworking and serious at times. When King joins the group, he starts to act like the only rational one in the group, and questions his teammates' erratic and slightly insane actions, such as their nonchalance about losing their sacred treasures. When forced to do something he dislikes, King can easily be motivated if it will make Diane happy. Despite King's kind personality, he is not against killing someone, if pushed to his limits. King was willing to kill Guila and Jericho if they continued to attack him, but was unable to after Helbram saved the two.
King was born more than a thousand years ago from the Sacred Tree of the Fairy King's Forest. At some point, he was chosen by the Sacred Tree to be the third Fairy King.
700 years ago
Seven hundred years ago, King was the ruler and guardian of the Fairy King's Forest; a country set on the border between the Fairy and Human realms. His spear, Chastiefol, was made from the Sacred Tree placed in its center. King used to live with Elaine along with other Fairies, keeping up the peace between them and the humans. During his time protecting the forest, King and Helbram were best friends. But unlike Helbram, King found no interest in humans and cautioned Helbram not to trust them. However, Helbram and his group went out of the forest to see the human world, where they met a group of human travelers who promised to give them items in exchange for information about the Fairy World. However, it was revealed that the humans were only after their wings, which could be sold for a lot of money, as it was believed to extend a person's lifespan. King then went out of the forest to save his friends despite Elaine's efforts to stop him, telling her to stay and protect the forest. After finding the dead bodies of the Fairies, King stumbled upon a tall, armored human wearing an eye patch named Aldrich who attacked him from the back, ending up nearly killing him, until he was saved by a young Diane. Due to his injuries, King ended up forgetting about his life as a Fairy King and spent his time playing with and protecting Diane.
Diane later met a stranger who offered them soup, despite them being a fairy and a giant. Feeling uneasy with the old man, King told Diane to be cautious around humans. When Diane came down with a fever, he was sent into panic due to the fairies' lack of understanding of diseases and sicknesses. However, Diane stopped him, telling him to not leave her side since she was always lonely. The old man who gave them food found them and offered some herbs for Diane to feel better. At this point, King realized that a human's time passed much faster than the other races, as the old man that he had met before had aged several decades since the last time he had given them soup. As soon as Diane got better, they ended up playing tag with each other. He told her that if she caught him, he would grant her a wish. Diane took it seriously and caught him, but ended up getting her clothes ripped, leaving her naked, much to his surprise. He decided to make her new clothes and went to the old man's place, only to find more towns built there, and that the old man had a grandchild now. After leaving the forest, he told Diane about marriage between two humans who love each other.
Diane asked if King loves her, to which the latter shyly nodded. Diane then asked him if he would always love her and stay by her side, which made him blush harder. Later that night, he finally remembered his identity and found out that the village close by is on fire. He told Diane to sit back and hurriedly went to the village, only to find out that everyone died with their backs slashed. King found the man who killed him years ago and was shocked to see him still alive. He then realized that it was Helbram using the identity of the person who hunted down the fairies for their wings. He got back up and decided to end Helbram's rage to humans, killing him in the end. King then went back to Diane to erase her memories of him, fearing that he will be unable to protect anyone anymore. King was then captured by unknown Holy Knights for the crime of "Sloth" as he was a king, and was unaware of Helbram's mass murder of humans, and turning a blind eye. Unaware at the time, one of those Holy Knights was Meliodas, with whom he would be properly introduced to after joining the Seven Deadly Sins. Additionally, due to his imprisonment, King was unable to return to the Fairy King's Forest and was absent during the events that lead to the Destruction of the Forest and the death of his sister, Elaine. Because of his absence, his own people began to resent and eventually hate him, overall ending his reign as their king.
15 years ago
King's sin eventually led him to become a member of the Seven Deadly Sins when King Liones formed the group. Despite being a former king, he was not assigned the role of the leader, and the group was led by Meliodas and supervised by the Great Holy Knight, Zaratras. Additionally, in meeting the other members of the Sins, King was introduced to Ban, who's immortality originally piqued his curiosity, yet he ultimately overlooked this fact due to the uniqueness of the other members and befriended him, unaware of Ban's connection to the Fairy King's Forest's destruction. King was also reintroduced to Diane, who at the time had no memories of their time together. From that point onward, King adopted and maintained a more human form to help prevent Diane from remembering their former past, which also led to some other Sins (mostly Ban and Gowther), as well as the majority of the Holy Knights of Liones, from ever seeing his true appearance as a fairy.
A long time ago, Ban went through a phase of collecting stuffed animals. He went around stealing every stuffed animal in the kingdom, thinking that he wouldn't be cursed if he did such a small deed as he worked hard as a knight. Immediately, King grew angry at Ban, complaining that the little children throughout town were crying. Whilst Ban finally grew satisfied and fell asleep, King silently returned all the stuffed toys to the children. Since then, King follows Ban wherever he goes to prevent him from causing trouble, giving other people the impression that they were the unlikely "dynamic" duo.
12 years ago
King and his teammates participated in a mission to wipe out a group of vampires at the castle of Edinburgh. During the attack, King was partnered with Diane and confronted the two Vampires, Mod and Ganne, however, due to Ban, who was very drunk, and had deliberately used Snatch to steal all his and Diane's strength as they were fighting, they were both struggling very hard to defeat them. Fortunately, they were saved by Gowther who had made the vampires believe he was a part of their family and had the two vampires attack and kill one another. Diane and King were then upset over Gowther for not coming sooner, who justified his actions by saying that he wanted to make it exciting.
Sometime later, after the training, King accompanied Ban to a bar where he angrily glared at the immortal who passed out drinking while Meliodas was talking to Hendrickson and Dreyfus. At some point in time, he and his fellow Sins met up with King Liones who was with young Elizabeth. King did not recognize her until Gowther revealed her identity ten years later.
10 years ago
At the day of the betrayal, King and the rest of his teammates were summoned by Great Holy Knight Zaratras to meet with him at the castle. While walking with his fellow members, he reminded his captain, Meliodas, that he is always drinking when the latter mentioned that they should have attended the National Foundation Festival. They entered the room together and saw a murdered Zaratras, much to everyone's surprise. King obeyed Meliodas' last order to separate and hide until they can regroup.
Ten years ago, after the incident, King went back to his hometown to see his old family and friends. He discovered that a bandit had stolen the hidden treasure, the Fountain of Youth, and had killed the Guardian Saint, who was his sister. King later found out that it was Ban who had killed his sister and decided to take revenge on him by joining the Holy Knights.
Abilities and Equipment
As a member of the Seven Deadly Sins and the current and most powerful Fairy King in all of history, King is extremely powerful. He is strong enough to overpower a Great Holy Knight single-handedly. Being a Fairy, King has demonstrated a number of abilities unique to his species; such as the ability to levitate or fly, the ability to change his appearance and clothes at will, as well as possessing great speed equal to Meliodas and Ban. Upon unleashing his true power, Meliodas and Ban commented that his strength grew to "an incredible level". This was later re-affirmed when he defeated Helbram, a Great Holy Knight level combatant while protecting all the injured in the area; then almost immediately after, swiftly defeated Dreyfus, one of the Great Holy Knights of Liones, despite the injuries he sustained from his battle with Helbram. During his reign as the Fairy King, his power was said to be so great that it kept the human kingdom from invading the Fairy King's Forest. It should be noted that this included the Holy Knights of Liones.
Despite his great power, King is physically weak, however, he makes up for his lack of strength with his sacred treasure, Spirit Spear Chastiefol, and his immense level of magic power. In spite of his lack of physical strength, he has shown a remarkable level of durability as shown in his second battle with Helbram. It was believed that King was able to control the Sacred Tree a long time ago and with it draw out the true power of a fairy, but the tree abandoned King for an unknown reason. This was later proven to be false as the Sacred Tree has no evil intentions at all and it was King who did not want to fully utilize the Sacred Tree's powers.
After going through the trial and his wings finally growing, King's power increased greatly, being able to freely access the true power of the Sacred Tree and his Sacred Treasure. Melascula states that his power became comparable to Gloxinia's. Gloxinia himself remarked that despite King's wings have only barely grown, he can wield his spirit spear on par with himself and thus would be capable of surpassing the first Fairy King and even becoming the most powerful Fairy King in all of history. This statement was later proven to be true, as after breaking Mael's seal and having his wings fully grown, his true potential was awakened, not only changing his appearance but the strength and quality of his powers greatly. This allowed him to not only overpower Mael with his Chastiefol but also to also use multiple Chastiefol forms simultaneously; for both offensive and defensive purposes, as he easily overwhelmed Mael in their fight while simultaneously protecting and defending Diane and everyone else from further harm during the battle.
King is extremely fast, as shown when he not only effortlessly evaded the attacks of both Guila and Jericho simultaneously but also knocked them unconscious before either of them could realize it. He is also able to keep up with fellow Sins Meliodas and Ban in terms of speed. Despite lacking physical strength, King possesses a remarkable level of durability and endurance as shown in the Kingdom Infiltration arc where he not only fought and defeated Helbram but also pinned down Dreyfus immediately after, despite the injuries he sustained against Helbram.
- Main article: Disaster
災厄Dizasutā」: An innate power granted to the fairy bestowed with the title "Fairy King". This ability essentially grants him the authority to rule over the Fairy King's Forest and allows King to exercise complete control over life and death by altering and controlling matter at a molecular level. For example, he can turn a shallow scratch into a fatal wound, a minor poison into a lethal toxin, and a small benign growth into a cancerous tumor that can devour a body whole. It also gives him complete control over nature, allowing him to manipulate various flora, letting it flourish or perish in moments. This power was originally described as the reason that King is able to completely draw out the mysterious qualities of the Spirit Spear, Chastiefol, as Disaster can modify the natural status of something and can change its shape.
- Levitation: King possesses the ability to levitate and is capable of flight because he is a fairy. He demonstrates great skill in using it and is able to move quickly through the air. He can also utilize this ability to levitate objects and manipulate their trajectory without the need to make any direct contact.
- Transformation: An ability that allows King to change his physical appearance as well as his clothes. In order for King to change appearance, he requires a great amount of concentration. This ability appears to leave him exhausted, however, King was able to maintain his transformed appearance for quite a while ten years ago, implying he has immense willpower. Somehow King shifted to human form almost randomly in either comedic or serious situations.
- Heart Reading: As a fairy, King can read the true thoughts and feelings of others. After awakening his true potential, his control and use of this ability was greatly magnified, as he not only read Diane's thoughts, but also Mael's thoughts, being the only one around Mael capable of hearing and understanding him in his transformed form.
- Dancing Fairy「
踊る妖精Danshingu Fearī」: A fight dance that has been passed down through the Fairy Clan for generations. Using this technique, King leaps into the air and charges at his opponent while rapidly jabbing with his fists. It is very weak and the charge can be stopped with one finger.
- Chastiefol: King's sacred treasure, the Spirit Spear, Chastiefol, is a spear crafted from the sacred tree, only found in the Fairy Realm. It is much stronger than steel and possesses the mysterious qualities of the tree, which King's ability, Disaster, draws out. It has several different forms, including a pillow which can act as a shield, different forms of spears, and a large stuffed grizzly bear.
- Helbram's Helmet: After King killed Helbram for the third time, King took Helbram's helmet and attached it to his coat's hood. In the helmet resided the spirit of Helbram, and King could put on the helmet to get in contact with his deceased friend. However, the helmet was destroyed when Helbram's spirit sacrificed himself to free Diane from the grudge of Corand.
Upon releasing Chastiefol's true form, his Power Level momentarily doubled that of an Albion's. Therefore it was between 11,000 and 12,000.
After passing the trial and his wings grew slightly, his power levels were as follows:
King and Meliodas are both members of the Seven Deadly Sins. King enjoyed his time with Meliodas in the past and still cares about him to this day. When King joins up with the group, he occasionally disagrees with Meliodas' actions, but still trusts him as a good captain. After Vaizel, King struggles with the fact that Meliodas could be a demon himself. Despite finding Meliodas' perverted antics shameful, King still respects Meliodas for that shameful nature since King is too shy to be bold for Diane and wants Meliodas to teach him to be bolder. However, after finding Meliodas relates to the Ten Commandments, King starts to question Meliodas' true nature and whether or not he is on their side. It doesn't help when Meliodas refuses to tell him and instead questions his title as king of the Fairies. King decided to be on Meliodas' side since Diane and Ban trust him, but warn Meliodas that if he betrays them, King will kill him.
Despite having mixed feelings over Meliodas' true nature, he was troubled to see Meliodas get beaten by the Ten Commandments and shed tears when he died, showing that deep down, King still cared about Meliodas as a captain and friend. After passing his trial, and learning about Meliodas and Elizabeth's curse, King finally understood his captain better and deeply regretted how he treated Meliodas prior to learning about his past, and as a result, his mixed feelings towards Meliodas have subsided, now fully trusting him as a close friend once again.
King and Diane are both members of the Seven Deadly Sins. King is in love with Diane but is too shy to reveal it. When King is forced to do something he dislikes, he can easily be motivated if it will make Diane happy. King is shown to comfort Diane whenever she is hurt or upset. When Diane was ruthlessly beaten and near death, King was willing to use all of his powers to protect her. In the past, King looked after the young Diane for five hundred years after she saved and took care of him until he was fully healed. When they meet up again ten years later, he still loves her and finds her just as adorable as she was a decade ago. Soon after defeating Helbram, Diane regains her memories and falls in love with King. King is dedicated to protecting and loving Diane. They eventually kiss and become a couple. Even after losing her memories once again due to the actions of Gowther, Diane grew fond of King quickly when she saw how determined he was to protect her during their battle at the Great Fighting Festival, seeing him not only as her friend and ally but as someone very close to her. After the two of them underwent their trials from Drole and Gloxinia, Diane's memories were completely restored, as she immediately kissed King after explaining that her memories were back, signifying that her love for him has grown.
King and Ban are both members of the Seven Deadly Sins. He hated Ban and wanted to kill him, in order to avenge his sister Elaine who was believed to be killed by Ban - even though she actually died because of a Demon's purgatory fire. When Elaine told him to protect Ban and join up with the group, King reluctantly accepts her request and assists the fight against Guila. Although he no longer despises Ban as much, he still feels uncomfortable around him. As time progresses, two become closer than they were before, as King eventually learns the whole story between him and his sister, how they loved each other, and was even shocked by how determined Ban was to bring Elaine back to life. He accompanied Ban on his journey to restore the Fairy King's Forest, and was even shocked when Ban actually accomplished this goal. He was even more shocked by Elaine's return and Ban and Elaine's love for one another, and as a result, King now truly respects and has befriended Ban.
King and Gowther are both members of the Seven Deadly Sins. King is shown to be annoyed at Gowther's clueless nature and Gowther's revealing of secrets. King grew furious at Gowther for erasing Diane's memories, but at the same time, knew he was no better. However, their relationship was strained due to Gowther's actions. After passing his trial, and learning more about the holy war and Gowther's past involvement in it, he finally understood Gowther's behavior better, and despite not fully forgiving him for erasing Diane's memories, he was more than willing to assist Diane in helping Gowther deal with the return of his memories and emotions.
King and Merlin are both members of the Seven Deadly Sins. Like the others, King respects Merlin greatly and is fully aware of her abilities. He has no hesitation to consult her when needed as seen when he resorted to her for a solution to Diane's amnesia.
King and Escanor are both members of the Seven Deadly Sins. Not much has been revealed between the two, but it appears that King is somewhat weary of Escanor, as he goes berserk during the daytime.
Elaine is King's sister, who he left at the Fairy King's Forest for 700 years, protecting the Fountain of Youth. King loved his sister so much that he was upset at the discovery of her death, vowing to avenge her by killing Ban, who was reported to be the one who killed her. Despite wanting Ban dead, he respected and accepted Elaine's request to help and protect Ban during the fight against Guila. After learning the truth behind Elaine's death, his hatred of Ban slowly disappeared, especially after learning of his intent to revive her, as well as his promise to restore the Fairy King's Forest for her. After learning of Elaine's revival, the siblings met once again at Vaizel during the Great Fighting Festival and were happy to be reunited with each other once again.
King is Oslo's master and is very loyal to him. Oslo knew King many years before he met the Seven Deadly Sins, in the Fairy Realm. King cared for Oslo so much that Oslo was also a part of the reason why King was able to fully grow out his wings. Oslo's loyalty is also shown when he sacrificed himself.
King and Elizabeth share fairly good friendships. King greatly respects her for being a princess of the royal family and her bravery for trying to pull his spear to help the Sins. He is concerned for her well-being, as shown when he assists Meliodas in saving her from the Ceramic Tear Inn after she was captured by Griamore. When they were properly introduced, King was shocked to find out her identity and apologized for his 'rudeness' earlier before transforming into his human form, wearing royal attire to greet Elizabeth formally, believing that it was more respectful.
King and Hawk seem to share a good friendship, and sometimes King calls him Mr. Pig, Little Porker, or Little Piggy. King showed some respect for Hawk for trying to pull his spear to help Elizabeth to help the Sins, but he shows more respect towards Elizabeth.
Several years ago, King and Helbram were best friends, despite having different views on humans. Helbram trusted King very much, but frequently teased him. Gowther mentions that Helbram is the reason he was unable to use his full power. When King believed he killed Helbram, he decided to atone for his sins and was sentenced to imprisonment for one thousand years.
As the Original Fairy King, and as a member of the Ten Commandments, King saw Gloxinia as a powerful enemy. King was visibly surprised by the difference in power between himself and the former Fairy King. This was seen during the Great Fighting Festival arc when he saw the extent of Gloxinia's healing abilities on Escanor, his abilities to form flower and wood golems for battle, as well as the different forms and abilities of his Spirit Spear Basquias. Later when Gloxinia and Drole approached King and Diane in battle, King managed to impress Gloxinia with his readiness to battle him, however, he shrugged off most of King's attacks towards him, stating that King could be stronger than he currently is if he had his wings, a statement which upset King. During his trial, King could feel the significant difference in power between his own body and Gloxinia, and also learned a lot about Gloxinia's past and the similarities between the two of them. After King passed his trial and his wings grew, both King and Gloxinia's opinions towards one another changed, due to their similar pasts. King now viewed Gloxinia as an ally and even trusted him enough to look after the Fairy King's Forest while he continued his fight with the remaining members of the Ten Commandments. Gloxinia also now seems to hold King in high regards, as he came to his rescue during the fight against Chandler, and his final words to King were how even though his wings had just grown, his power has now become comparable to his own, that eventually as they grow he would slowly, but definitely become the most powerful Fairy King of all times, a statement that King was visibly surprised by.
- King vs. Albion: Win
- Meliodas vs. King: Indecisive
Great Fight Festival arc
Prelude to the New Holy War arc
- Seven Deadly Sins vs. Chandler: Indecisive
- Search-and-Destroy Force vs. Demons: Win
- Gowther, King, Sariel, Tarmiel & Derieri vs. Mael: Lose
- Gowther, King, Diane & Elizabeth vs. Mael: Win
- Seven Deadly Sins & Four Archangels vs. Zeldris & Original Demon: Win
- Seven Deadly Sins, Four Archangels & Zeldris vs. Demon King: Win
Demon King arc
Prisoners of the Sky
- King & Diane vs. Galla: Win
- King & Gowther vs. Atollah: Win
- As the Fairy King, King's lifespan is relatively longer than any of the other races.
- The reason King and Elaine's wings haven't come out yet because they are considered late bloomers.
- The technique Bumblebee connects with the color of King's sacred treasure which is the color of bees.
- According to the databook(s):
- Special skill: Sleeping huddled
- Hobbies: Observing Diane and his Daily Routine is watching over her
- Weakness: Lack of muscles
- Birthplace: Fairy Realm
- What he likes about himself: His elegance (in his old man form)
- Dream/Hope: Marrying Diane
- Regrets: Too many
- The most embarrassing thing in his life: That he doesn’t have wings yet
- What he wants the most right now: Diane’s heart
- Favorite animal: None in particular
- Favorite scent: Diane’s cleavage
- Favorite food: Cheese
- Charm Point: Unruly strands of hair
- He has a complex about his childlike facial features
- The person he respects the most is the previous Fairy King, Dahlia
- A person he doesn't want to make an enemy of is Escanor.
- King once lost to a cat that stole his snacks.
- King has a sweet olive scented body odor in his child-like form, but a musty, sweaty smell in his chubbier form.
- King dislikes drunkards - this is one of the reasons he does not like Ban.
- King sleeps on a hammock beside the window on the third floor of the Boar Hat - an excuse to watch over Diane.
- King currently shares his room with Ban.
- King is skilled at sewing clothes, having made Diane's and his own outfit.
- Meliodas claims that King's hobby is peeking, which the latter denied.
- The Sin of Sloth is usually symbolized with a Goat and the color blue.
- In the Nanatsu no Taizai Popularity Poll, King was placed 1st overall with 121,945 votes (which included an online poll as well as postcards) and placed 4th (226 votes) when considering only postcards.