Shirahoshi is the princess of the Ryugu Kingdom and the youngest child and only daughter of the Neptune family. She is a giant-sized mermaid known for her incredible beauty and kind heart. As the “Mermaid Princess,” Shirahoshi is loved by the people of Fish-Man Island. Despite her timid and emotional personality, she is brave when it counts and cares deeply for others. Shirahoshi holds a special power that lets her communicate with Sea Kings, making her the Ancient Weapon “Poseidon.” Her journey is one of growth, courage, and finding friends who help her see the world in a new way.
Shirahoshi is a mermaid with an enormous size, standing at 11.87 meters (1,187 cm) tall.
She has long, flowing pink hair tied up with a taiyaki-shaped hair accessory.
Her eyes are big and gentle.
Though she is beautiful, her body shows traces of the Big Kiss fish, making her much larger than other mermaids.
She is known for her stylish and well-developed figure.
- Age: 16 years old
- Height: 11.87 meters (1,187 cm)
- Birthday: April 4th
- Zodiac Sign: Aries
- Blood Type: X
- Favorite food: Sea grape pasta
Shirahoshi is very timid and cries easily.
Luffy D. Monkey sometimes calls her “coward” or combines her name with “coward” as a nickname.
She is naive and doesn’t have much experience with the world, since she grew up protected in the palace.
Her social skills are not polished, so she often speaks her mind directly.
She struggles with lies and prefers being honest, even if it causes trouble.
Shirahoshi calls everyone “Sir” or “Madam,” even if they are close friends or even her enemies.
Despite seeming weak, she has a strong heart and will protect others, even putting herself in danger if needed.
She keeps mother Otohime’s last wish and refuses to hate or seek revenge, showing her inner strength.
Shirahoshi was born as the daughter of Neptune, king of the Ryugu Kingdom, and Queen Otohime.
Even from a young age, she was much bigger than her mother and brothers.
As she grew up, she often joined her mother’s speeches about living together peacefully with humans.
10 years ago, while Fish-Man Island was in trouble, Shirahoshi’s power to speak to Sea Kings first awakened when she tried to save her mother.
After that, Vander Decken IX targeted her, trying to force her to marry him, and used his powers to attack from afar.
She was forced to live locked inside the Hard-Shell Tower for 10 years to stay safe.
Shirahoshi has a rare and legendary ability to communicate and command Sea Kings.
This power appears only once in several centuries, in a mermaid known as "Poseidon."
With this power, she could potentially sink the world into the sea, but she is not aware of the full danger of her ability.
She is not a fighter and does not have strong self-defense skills.
Shirahoshi also holds the title of Ancient Weapon “Poseidon,” one of the three most powerful ancient weapons in the world.
Shirahoshi loves her family very much.
Her father is Neptune, the king, and her late mother is Otohime.
She has three older brothers: Fukaboshi, Ryuuboshi, and Manboshi, who are all strong princes who protect her and the kingdom.
She quickly trusts Luffy D. Monkey after he saves her and considers him a dear friend.
Shirahoshi makes new friends with princesses like Vivi Nefertari, Rebecca, and Mansherry at the Reverie.
The people of Fish-Man Island call her “Princess Shirahoshi” and adore her.
“My father… If I could… I would love to live on the surface!!!”
“I wish I could show this ‘world of the sun’ to everyone in the kingdom!!”
“What are you doing standing on top of someone's body!!?”
“You’re not my type…!!”
Early Life and Sea King Power
Shirahoshi was born on Fish-Man Island as the princess of the Ryugu Kingdom.
When she was young, she joined her mother Otohime in teaching about friendship with humans.
Ten years ago, during a crisis with Mjosgard Donquixote, Shirahoshi’s hidden power awakened for the first time.
She unintentionally saved her mother and others by calling upon the Sea Kings.
This event led Vander Decken IX to start targeting her to exploit her power.
After being marked by him and becoming the victim of his constant attacks, Shirahoshi had to live hidden in the Hard-Shell Tower for her own protection.
Tragedy and Hidden Sorrow
Shirahoshi could not attend Otohime’s public funeral due to her hiding.
Later, her pet shark Megalo revealed that Hody Jones was the true assassin.
Shirahoshi kept this a secret to fulfill her mother’s wish: Don’t let hate consume your heart.
She chose not to seek revenge or spread anger among her people.
Meeting Luffy D. Monkey and Breaking Free
Luffy D. Monkey enters Shirahoshi's tower by accident and offers to protect her.
With his help, she sneaks out, hiding inside her shark friend Megalo’s mouth.
She finally visits her mother’s grave and later, at Coral Hill, boldly rejects Vander Decken’s direct marriage proposal by saying, “You’re not my type!”
She, Luffy, and their friends help defend the kingdom against the New Fish-Man Pirates.
Battle at Gyoncorde Plaza and the Noah Arc
During the kingdom’s crisis, Shirahoshi and Luffy’s group go to save her captured father and brothers from Hody Jones and his followers.
When Hody confesses to killing Otohime, Shirahoshi bravely reveals the truth but refuses to hate him, honoring her mother’s wish.
Vander Decken tries to crush the island with the giant Noah ship, planning to destroy everything out of spite.
Shirahoshi bravely goes out to sea to help stop the Noah.
Her powers awaken, and she commands the Sea Kings to move the Noah away, saving Fish-Man Island from destruction.
After the fight, Nico Robin discovers and reveals that Shirahoshi is actually the Ancient Weapon “Poseidon.”
Leaving Fish-Man Island and Attending the Reverie
After the battle, Shirahoshi is almost kidnapped by Caribou, but Luffy saves her again.
When the Straw Hat Pirates leave Fish-Man Island, Shirahoshi bids them a heartfelt goodbye, promising to meet again.
The Reverie and Friendship with Other Princesses
Shirahoshi finally overcomes her fear and visits the surface for the first time to attend the World Conference (Reverie) with her brothers.
She is amazed by the sky and sun and wishes to show this beautiful world to everyone back home.
At the Reverie, she becomes close friends with Vivi Nefertari, Rebecca, and Mansherry, who are also princesses helped by Luffy.
Saint Charloss tries to capture her as a pet, but with help from Mjosgard Donquixote and her new friends, she is saved.
Returning Home
After the World Conference ends, Shirahoshi and her family return safely to Fish-Man Island.
She learns about trouble in Alabasta from Garp and continues to grow stronger through her experiences.
The author found it hard to draw “the most beautiful women” and struggled with designing Shirahoshi after Boa Hancock.
Shirahoshi’s unique “sad eyebrows” were created to give her a distinct style.
Despite being called weak, her strong will and kindness make her special.
Her popularity is high, with many fans loving her unique traits and courage.
First Appearance: ONE PIECE Volume 62, Chapter 612 "Led by the Shark I Saved".
She ranked 50th in the official character poll with 19,690 votes.
Shirahoshi’s design is inspired by big fish like the Big Kiss, which is unique to the story.
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