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Behind her appearance as a shy, tearful mermaid princess, Shirahoshi hides one of the best-kept secrets in the entire One Piece universe: she is Poseidon, one of the three Ancient Weapons capable of making the world tremble. Let's take a look back at a character who is far more strategic than she might initially appear. Approximately 7 minutes of reading.
Who is Shirahoshi?
The princess of the Ryugu Kingdom
Shirahoshi is the youngest daughter of King Neptune, ruler of the Ryugu Kingdom on Fish-Man Island. A mermaid of exceptional size, far beyond the norm even for her species, she grew up isolated from the outside world, constantly protected by a close-knit guard devoted to her safety.
A childhood marked by fear and isolation
This extreme protection was no coincidence: Shirahoshi grew up under the constant threat of assassination attempts, without always understanding why her mere existence represented such a danger. This context largely explains her anxious nature and tendency to burst into tears at the slightest incident.
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Poseidon, the Ancient Weapon sleeping within her
A unique ability: commanding the Sea Kings
As the incarnation of Poseidon, Shirahoshi possesses the extremely rare ability to communicate with the Sea Kings, gigantic creatures capable of ravaging entire fleets in an instant. Our article on the three Ancient Weapons explains how this power works and its strategic importance for anyone seeking to dominate the seas.
Why this identity remained secret for so long
The World Government has been trying for decades to get its hands on the three Ancient Weapons, which explains why Shirahoshi's identity as Poseidon was kept secret for as long as possible, including from Shirahoshi herself for much of her childhood.
Did you know?
Shirahoshi's unusual size, far greater than that of the other mermaids in her kingdom, is directly linked to her nature as the incarnation of Poseidon rather than being a simple physical peculiarity.
A fragile princess who becomes an unlikely heroine
A character who grows throughout the arc
Far from remaining a mere passive figure to be protected, Shirahoshi undergoes considerable growth throughout her arc, gradually gaining confidence through her encounter with Luffy's crew. This transformation, from an inconspicuous princess to someone capable of embracing her own destiny, remains one of the most touching character arcs in this part of the series.
The moment when she literally saves the island
Faced with the threat of a tsunami caused by a tribute ship intended for Big Mom, Shirahoshi uses her power to summon the Sea Kings to the rescue for the first time at its full potential, thereby saving Fish-Man Island from certain destruction. Our article on the prophecy of Fish-Man Island looks back at this pivotal episode and the legend surrounding Luffy's arrival in this kingdom.
⚓ Fan favorite
One Piece Figure — Monkey D. Luffy Gear 5 Nika (Smoke Effect)
34,99 €
The captain who managed to restore Princess Shirahoshi of Ryugu's confidence during their very first encounter.
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The bond that unites her with Luffy
A simple but essential promise
The relationship between Luffy and Shirahoshi is built on a disarmingly simple promise: to protect her and believe in her, without ever seeking to exploit her status as an Ancient Weapon. This approach stands in stark contrast to that of the World Government, which is more interested in the power she represents than in the person herself.
A choice that could have a major impact on the rest of the story
By earning Shirahoshi's trust rather than her submission, Luffy could potentially secure a powerful ally for the rest of his journey to Laugh Tale—an alliance that could prove decisive if the World Government were to forcibly bring together the three Ancient Weapons. This bond of trust also recalls what led Jinbe, another major figure from Fish-Man Island, to ultimately join Luffy's crew.
One Piece Figurine — Gear 5 Nika (Free Combat Pose)
★★★★★ — The symbol of an alliance born beneath the seas
39,99 €
A dynamic pose that recalls the promise made to the princess of Ryugu, long before the revelation of Gear 5.
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Why her role could still have a major impact on what comes next
With the revelations surrounding the Void Century and the growing importance of the Ancient Weapons in the main storyline, Shirahoshi could well become a central figure again in upcoming arcs, particularly if Luffy and his crew find themselves in a position to assemble all three weapons to oppose the World Government.
Delve deeper into the lore surrounding the Ancient Weapons
Our Devil Fruit and Haki guide helps explain the power mechanics surrounding characters like Shirahoshi, while our One Piece quiz lets you test your knowledge of the three Ancient Weapons and their respective wielders. Our page on One Piece arcs in order helps place Fish-Man Island within the broader chronology of the journey, while our page dedicated to the Straw Hat crew shows how each member experienced this particularly unique arc. Our gift ideas selection also offers several items inspired by the world of the Fish-Men for fans especially attached to this arc, alongside the Gear 5 Nika on Cloud figurine, which recalls the lightness Luffy regained after his journey beneath the seas.
Frequently Asked Questions
Answers to the most frequently asked questions about Shirahoshi.
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