Monkey D. Aika is a young pirate-in-training, and the cabin girl of the Straw Hat Pirates, being one of the crew's three youngest members. She is the younger half-sister of Monkey D. Luffy, daughter of Monkey D. Dragon and Kamiya, half-granddaughter of Monkey D. Garp, adoptive younger half-sister of Portgas D. Ace and Sabo, and owner of the young Akita puppy, Kumi. Her dream is to become a great pirate like her older brother when she grows older, as she continues to be brave and standing up for what's right in the midst of a crisis no matter how many times others tell her to stay put.
Monkey D. Aika

Profile and StatsEdit

  • Alias: Wolf Princess
  • Origin: One Piece
  • Gender: Female
  • Age: 6
  • Birthday: May 3
  • Classification: Human, Zoan Devil Fruit User, Straw Hat Pirates Cabin Girl and Trainee
  • Height: 106 cm (3'6")
  • Weight: 39 kg (86 lb)
  • B-W-H- Measurement(s): 50-35-50
  • Skin Color: Pale
  • Eye Color: Brown; Golden-Yellow (Wolf Form)
  • Hair Color: Black; Dark Blue and Tan Coat with Cream Underbelly and Muzzle (Wolf Form)
  • Attire: Dark red cowgirl hat, bright-blue butterfly clip, sky blue T-shirt with the word "DOG" written in big white letters on the front, magenta skirt with a pink, cherry blossom print on it, black sneakers with white laces and white socks
  • Alignment: Good
  • Status: Active
  • Powers and Abilities: Dog-Dog Fruit: Honshu Wolf Model, Haki (Observation and Conqueror's), Hand-to-Hand Combatant, Enhanced Speed and Reflexes, Enhanced Durability, Enhanced Endurance, Enhanced Smell, Enhanced Sight, Expert Homemaking Skills, Swordsmanship Skills, Marksmanship Skills, Driving Skills
  • Standard Equipment: Metal Pipe
  • Weaknesses: Aika cannot swim and becomes immobilized if more than half of his body is covered in water. Very timid and scared when seeing Marines, but is starting to overcome that weakness in certain moments.

Power RankingEdit

  • ClassC-Class
  • Attack PotencyAthlete level | At least Athlete level
  • Speed: Athlete with Subsonic reaction speed | Likely Subsonic with Supersonic+ combat speed
  • Lifting Strength: Below Average
  • Striking Strength: Class H | Possibly Class KJ
  • Durability: Small Building level | Small Building level
  • Stamina: Peak Human
  • Range: Human Range
  • Intelligence: Average
  • Fighting AbilityTrainee
  • KeyBase | Zoan Form


Aika is a short, petite young girl who shares a striking resemblance to her half-older brother, except she has pale skin, bright and large brown eyes, long, dark hair that reaches down to her hip, and a bright-blue butterfly clip on the right side of her hair.

Like Nami and Robin, she changes her clothes daily, but mainly wears a dark red cowgirl hat on top of her head, a simple sky blue T-shirt with the word "DOG" written in big white letters on the front, a magenta skirt with a pink, cherry blossom print on it, and a pair of black sneakers with white laces on top of white socks rolled up to her calves.

When using her Devil Fruit powers, her appearance is changed. She has the form of the extinct honshu wolf, with tan coated fur around her body with a cream-colored underbelly and muzzle, two pricked ears, and a shiny gray nose. Her black hair now becomes a blackish-blue color, and her eyes now become golden-yellow with a vibrant aura. She maintains her butterfly clip and only keeps her top clothing; the bottom portion of her clothing disappear, but will reappear if she turns to her human form.


Much like her boisterous brother, Aika is a cheerful, carefree, silly and optimistic young girl, with a peculiar mind when observing things from her perspective and a gluttonous appetite for food (mainly cookies). She is quick to make new friends and is more than willing to help those in need whenever she can, even risking her own life to ensure their safety at such a young age. She takes the time to reflect about her surroundings, concluding to insightful wisdom(s) about love and bonds. Because she wants to help her crew and not be unless to them, she can be very reckless and stubborn, refusing to listen to those older than her because of her determination to help her friends and not wanting to suffer what she suffered. As a person with the middle initial D., Aika also has the common trait of not fearing death, always staying true to her word and tends to keep promises to those she calls her friends. She would even laugh in the face of danger and keep a smile on her face to stay well, despite being afraid on the inside.

Also, due to eating her Devil Fruit, Aika has developed a preference for being in her animal form more, especially after meeting the Straw Hats, and because of this, she has feral tendencies for hunting small prey, but she does not experience for killing her quarry, opting instead to release them after catching them. Aika, like Luffy, also has a tendency to wander off, as well as cause Kumi to follow her in an attempts to protect her. This often causes problems for the Straw Hats, for it tends to put them both in great danger that the older members have to get them out of. Luffy, ever thickheaded, claims he doesn't know where she gets this habit from, causing the other Straw Hats to glare at him in annoyance. This shows that Aika has imprinted some of Luffy's bad habits, as most children who admire their older siblings do.

When first introduced, Aika was very timid and afraid, talking only to her best friend Kumi, and being shy when trying to speak with someone new. This is because of her isolation after the loss of her family and being rejected by the other children due to her Devil Fruit powers; she knows better of knowing what it's like to suffer. This however changed when she met Luffy the first time (who she doesn't know as her older half-brother) and gave her the courage to speak for herself. Following Caesar Clown's defeat, she was welcomed by the Straw Hat Pirates and now became a member of their crew, which helps her continue to grow and become a more open person. Because she is so young, she has a questionable mind when hearing things that are suppose to be said when she is older, like hearing coarse language, sex, drugs or even blood makes her wanting to ask her more older friends what each one is, making them tempting to tell her in her later years as a teenager.

The one thing that Aika fears the most in her life is the Marines, especially their fleet admiralAkainu (the man responsible for the death of her mother and the islanders because of her heritage to Dragon). Whenever she sees the insignia, she will have a mental breakdown and relapse into her timid nature for about an hour. Even mentioning the Marines makes Aika afraid and scared, causing her friends to hide her inside the Thousand Sunny until it's safe, proven her fear after what she had suffered one year ago. Over time, she becomes less afraid and is more than willing to fight them, even standing up for her friends and brother despite their attempts to keep her safe. Despite hating the Marines, she knows there are some that aren't evil and only do it based on their convictions, as seen in her relations with Smoker and Tashigi.


Early LifeEdit


Dog-Dog Fruit: Honshu Wolf Model: A Zoan type Devil Fruit, this fruit allows the user to transform into a honshu wolf, whose strength, speed and senses are equivalent to that of an actual wolf. In her full animal form, she is more adapted to traveling in rugged terrain, such as forests and tundras. Having a Carnivorous Zoan makes her more predatory and bloodthirsty, which is called "Berserker Mode", and in this state, she gains a rush of adrenaline, but cannot tell the difference between friend and foe, although she hasn't shown this weakness yet.

Haki: There are normally two types of Haki regular people can tap into: the Observation Haki which allows individuals to sense the presence of others, and Armament Haki which allows individuals to create an invisible armor around them. There is however a third type of Haki, Conqueror's Haki, that only a few individuals can use. Despite her young age, Aika is one of these people to learn Conqueror's Haki.

  • Conqueror's Haki: The ability to knock out someone else or a large group. While inexperienced users are restricted to intimidating one being or blindly knocking out any with weak wills around them, those with more expertise can pick out weak willed individuals in a large group to knock out. Can also be used as an AOE energy blast and to tame animals.
  • Observation Haki: A form of Haki that allows the user to sense the presence of his opponents. A user of this type of Haki can predict an opponent’s moves before he gets hit. This works by showing the user an image or brief “premonition” of what the opponent will do, manifested as a mental image in the user’s mind’s eye, and the damage the user will take if the attack “hit” for real. It appears that the more killer intent the enemy has the easier they are to predict, though more efficient users can predict future moves regardless whether there are ambient murderous intents or not. Including the distance, location, and where the opponent may strike next.


  • Kamiya - Aika's mother. Aika loved her mother with all her heart, and Kamiya returned her unconditional love, and the pain she felt when she lost her hurt worse than any other pain she had felt before, and thus caused Aika to believe she no longer had a reason to live until she found out about her relation to Luffy. At times, Aika would sing songs that her mother used to sing for her back when they lived on Wolf Paw Island together, as a way to keep her memory alive.
  • Monkey D. Dragon - Aika has never met her father, before. In fact, she doesn't even know about him, but she expresses a desire to meet him, one day. However, she is unaware that Luffy hates Dragon, but he doesn't tell her anything about this grudge because he wants Aika to judge Dragon for herself.
  • Kumi - Kumi seems to be more than just a pet for Aika and is more like her best friend, as Blizzard is to Luffy. Before the Straw Hats came to Punk Hazard, Aika seemed to look to Kumi for advice. That changed after they joined up with the Straw Hats, when Aika started to grow in confidence, and Kumi began to turn into the follower instead of the leader. Still, the two are inseparable and are hardly seen apart.
  • Monkey D. Luffy - Aika and Luffy absolutely adore each other. Even before they found out about their relation to each other, they had an instant connection, especially when Aika showed Luffy her wolf form, which she has never done in front of anyone else except Kumi. Upon learning that Luffy is actually her older half-brother, Aika was so overjoyed that she burst into tears and ran into his arms, sobbing happily. Ever since, Luffy has vowed to love and protect the way Ace did for him, and promises her that he won't die and leave her alone. Aika greatly admires Luffy for his courage and sense of freedom, something she has taken to heart. However, she has shown that she has also imprinted some of his bad habits, such as wandering off without telling anyone and putting herself in danger, causing the Straw Hats to comically note how Aika truly is Luffy's half-sister, but Luffy claims that he doesn't know where she gets it from.
  • Sabo - After meeting Sabo, Aika is thrilled to have another older brother to love, even though she was told that Sabo had died 12 years ago. She notices that Sabo expresses sadness at his failure for not being able to rescue her mother and neighbors from the Buster Call, and was also afraid that he had lost Aika as well. Aika doesn't hold it against him, though, telling him that it probably wouldn't have mattered.
  • Portgas D. Ace - Aika was told about Ace's sacrifice by Luffy. After learning of her relation to Luffy, Aika was saddened in knowing that she never got to meet her other older brother, but she also expressed gratitude to Ace for saving Luffy's life, 2 years ago.
  • Koala - Aika sees Koala as another older sister-figure, aside from Nami. She is amazed by her prowess in using Fishman Karate and even calls her "Big Sis Koala" as soon as they met. As for Koala herself, she adores Aika for her charm and optimism, but she worries that her time with the Straw Hats will change her outlook on life.
  • Nojiko - Aika has only heard about Nojiko through Nami, but has expressed a desire to meet her ever since, excited about how big her family is.
  • Roronoa Zoro - Zoro finds Aika a bit irritating, due to her sharing the same traits as Luffy, such as doodling on his face while he sleeps. However, he also sees Aika as a child who has great potential, but due to his gruff nature, he tends to be a little too blunt with her at times. Whenever she is left in his care, though, Zoro tends to be more vigilant with her and becomes fiercely protective when an enemy is nearby, as shown when he fought off a troop of Marines to protect her. At times, the two are seen sharing a nap together, with Aika either resting in Zoro's lap or on his chest. This usually gains teasing from Sanji, who quips that Zoro might've gone soft, but this usually ends up with the two getting into an argument. Robin, meanwhile, notes that spending time with Aika has made Zoro act more fatherly.
  • Nami - Nami and Aika have a strong sisterly bond, both loving each other very much. Aika has even called Nami "Big Sis Nami" after they had bonded so much. Aika greatly admires Nami for her strong-willed and sassy nature, as well as her strength and beauty, even saying how much she wants to be like her when she gets older. Like Koala, Nami fears that the life of a pirate will change Aika for the worse, but when she sees her out playing like a normal child would, it only reassures that she has nothing to fear. Upon finding out that Luffy plans on training her so she can participate in fights, Nami was greatly against it, fearing for the little girl's life. It took some convincing from Luffy and Robin to reassure her that it was for Aika's own good, though. Nami expresses a desire for Luffy to be a good role model for Aika, although she contrarily isn't doing very good on this aspect, herself, for she has actually been teaching Aika to use her feminine charms to take advantage of people, something that Robin calls her out on.
  • Usopp - Aika is easily entranced by Usopp's tall tales, even though she doesn't exactly believe them. Even when she finds out they are exaggerated, she doesn't get mad. She likes to listen to them, especially before bedtime or when she gets sick and needs cheering up. More often than not, they end up getting into some silly antic together, such as paint fights or drawing on Zoro's face, which usually ends up getting them both in trouble with Nami. Usopp sees Aika as a confidant of sorts, feeling like he can truly be himself around her and even share deep secrets with her. Whenever this happens, they often go to sit in the Mini Merry II together to have some one-on-one time. As for Aika, she believes that Usopp truly does have courage inside him, even if he doesn't believe it himself. He feared that if he didn't lie about himself, Aika wouldn't see him as someone to look up to, but she assures him that he'll always one of her greatest friends.
  • Vinsmoke Sanji - Sanji is like a father figure to Aika, letting her sit in the kitchen and watch him cook, even letting her assist at times, be it adding ingredients or licking cake mix off bowls and spoons. Sanji has even taught Aika how to cook meals, in the even that he cannot cook or if is he absent from duty. Sanji treats Aika as a "young mademoiselle", being courteous and patient with her, and not even getting mad when she makes mistakes. Aika loves to hang out with Sanji in the kitchen, helping him out with washing the dishes and setting up the table for him, which in turn Sanji rewards her with treats, such as cookies. Sanji notes that Aika is more polite than Luffy when it comes to table manners, something he wishes Luffy would use more often.
  • Tony Tony Chopper - Aika absolutely adores Chopper and will hug him like he is a stuffed animal (but sometimes, she will hug a little too tight). They both have a mutual affinity for Cherry Blossoms and sweets.
  • Nico Robin - Aika loves Robin like a second mother, for they both have a checkered past that had to do with the Buster Call, thus Robin understands Aika more than anybody. She even accidentally called Robin "Mommy" due to being half-asleep one morning, which touched Robin because she didn't realize how much she meant to the child until that moment.
  • Franky - Like most girls, Aika is not easily impressed by Franky's "SUPER" body, and yet she loves the vehicles he has built and will sometimes be seen riding along with him on one. So far, her favorite seems to be the Black Rhino FR-U V.
  • Blizzard - Due to them being part wolf, Aika sees Blizzard as a teacher of sorts, learning how to fight and live like him. Sometimes, however, she will play with his hair and put little ribbons in it. However, Blizzard is patient with her and takes it all in stride.
  • Brook - Aika and Brook both have a taste in music, and are often seen playing the piano together. In some cases, Aika will even sing a song while Brook plays.
  • Trafalgar Law - Aika has shown that she has bonded with Law, as well. Even though Law won't admit it, he has actually grown quite fond of Aika because he reminds her so much of his late sister, Trafalgar Lamie.
  • Jupiter - Like with Blizzard, Aika will sometimes decorate Jupiter's hair, too. Unfortunately, he is not as patient with her as Blizzard is, so he might snap at her at occasion.
  • Tashigi - Despite her being a Marine, Aika can sense Tashigi is not one of the corrupt ones, and while she didn't go with her, she trusted Tashigi with the safety of the other kids. Tashigi allowed the Straw Hats to take Aika and Kumi, but only on the condition that she doesn't get involved with their escapades, for she does not want to see Aika's face on a wanted poster.
  • Smoker - Despite him being a Marine, Aika can sense that Smoker is not one of the corrupt ones. However, she is a bit frightened of him due to his gruff demeanor. Like Luffy, she likes to call him "Smokey".
  • Rebecca - Aika admires Rebecca for being strong enough to fight her own battles, despite her family's past. She understands what it's like to be bullied, which is one reason why she cheered for Rebecca during her fight in Block D during the Corrida Coliseum Battle Royale in Dressrosa. When Doflamingo unleashed the Birdcage on the country, Rebecca stood her ground long enough to try and protect from Diamante, but when she tried to go and help her and Kumi, only to get attacked. When the time came for the Straw Hats to escape the country after Doflamingo's defeat, Aika gave Rebecca one last parting gift: a flower necklace.
  • Carla - A girl who was turned into a fox plush by Sugar, Aika befriended her when she wanted to find a way inside the coliseum in order to watch Luffy and Blizzard fight during the Block C match. After Carla was returned to her human form and Doflamingo was defeated, they were seen making flower necklaces together, implying that they got along quite well.
  • Lucky - Sabo's pet dog. Aika was grateful to Lucky for helping save her life when she was attacked by Rita. They did not have very much contact, but she hopes to meet him again, someday.
  • Akainu - The very man who ruined Aika's life and killed her mother. When Aika first met Sakazuki, he was destroying her hometown on Wolf Paw Island, trying to hunt her down so that he could kill her himself. Because Aika is Dragon's daughter, Sakazuki deemed her very existence as a crime, thus leading him to issue a Buster Call to her home. The very mention of the Fleet Admiral's name sends Aika into a panic, revealing that their encounter had deeply traumatized her. It's due to this reason that has fueled Luffy's hatred for Sakazuki even more, which also fueled one of the three reasons Natsu Dragneel hates him far greater than Luffy.
  • Caesar Clown - Aika had become Caesar's enemy after she ate one of his artificial Devil Fruits and she refuses to let him conduct any experiments on her. Due to being the only one who caught on to his lies, Caesar saw even Aika as a threat to his operation, knowing that it wouldn't be long until the other children would believe her as well. The mad scientist even tried to kill her using a gas chamber, but luckily, Luffy arrived in time to rescue her. She even cheered when Caesar was finally defeated.
  • Donquixote Doflamingo - Aika expressed disgust over Doflamingo's way of thinking, seeing him as the evil man he truly was. She even snapped at him when he shot Law right in the middle of a busy square, which nearly cost her arm had Luffy not pulled her away in time. Doflamingo didn't see her as too big a threat, though, consider he only put a one-star bounty on her during the Birdcage game.
  • Buffalo - Despite their brief confrontation, Aika made a quick enemy out of Buffalo when he saw the 1-star on her head that Doflamingo put on her, he immediately chased her and Kumi. Thankfully, Koala was there to save them.
  • Rita - Doflamingo's pet saber tooth tiger, who hunted Aika and Kumi during the climactic battles. During this time, while Blizzard, Jupiter, and Lucky fought with Rita, Aika went into a berserk rage and even went as far to bite off the cat's ear. However, she had no memory of what had transpired, believing that Rita had knocked her out with a kick to the head.



  • "Big Brother!"
  • "Can we be friends?"
  • "I wanna be stronger!"