Isuka is a young woman with short vermilion hair, brown eyes, a bandaid on her left cheek and a burn scar on the back of her hand. She typically wears a Marine uniform with a collared, buttoned shirt, a tie, brown gloves, shorts and heeled boots. On her shoulders she wears the standard Marine coat with "Justice" (正義 Seigi?) on the back.
Isuka is a brave woman with a strong sense of justice, as she was willing to confront the Spade Pirates alone on their ship in order to arrest Portgas D. Ace. She is very tenacious and dedicated, because she kept chasing Ace through the first half of the Grand Line. However, she can also be a little clumsy and naive, as she expected Ace to come out of his ship to confront her, not realizing he snuck away from the other side.
Isuka prioritizes saving fellow Marines and civilians over capturing criminals, and is horrified at Draw causing unnecessary casualties while fighting pirates. She also believes that those on the side of justice should not resort to taking hostages.
When Isuka was a young girl, Draw saved her from a fire that he started, which burned her village down and killed her parents. Unaware that he started the fire, Isuka looked up to him and joined the Marines so she could rescue people from pirates. However, when Draw revealed his willingness to start fires, she realized that he burned down her village and broke down in tears. As the two have rarely interacted, Draw does not seem to put any thought into what his rescue of Isuka meant to her while it is unknown how Isuka views Draw after his defeat.
Portgas D. Ace
Ace and Isuka's relationship was similar to Luffy and Smoker's relationship, except on more amicable terms. She attacked Ace and his crew, viewing it as her duty to enforce justice. When she almost drowned, Ace threw her a life preserver, causing her to change her view about him. She attacked his crew several times since then, but Ace easily dealt with her with no grudges. Isuka then decided to try to get Ace to give up piracy, seeing him as a good person. After Ace stopped Draw's assault, Ace offered her a spot in his crew but she declined and parted ways with him on good terms.
Abilities and Powers
Isuka is a skilled swordswoman who fights by piercing her opponent full of holes with a rapier, earning her the epithet "Nailing".
Isuka wields a rapier in combat.
When Isuka was a little girl, her village was burned down by a fire caused by Marine Lieutenant Commander Draw, during a pirate attack. Her parents were killed, but she was saved by Draw. She received a burn scar on her hand during the attack.
At an unknown point, she joined the Marines and was promoted to the rank of Ensign.
At one point, while the Spade Pirates were throwing a party, Isuka infiltrated their ship. While the ship was being pursued by marine warships, she was easily fending off the Pirates onboard; she easily blocks a shot fired by Mihar, and Skull recognized her as "Nailing Isuka", a name she earned because she uses her rapier to leave people's bodies full of holes. Isuka prepares to arrest Ace and his crew, but Ace is not scared and cracks jokes. Isuka attacks Ace with fast attacks, and is unable to hit him due to him turning his body into flames, but she is able to dodge the Spade Pirates when they try attacking her in return.
The Marine warships catch up to the Piece of Spadille and begin attacking, as Isuka had come onboard earlier to distract the Spade Pirates from the warships' approach. However, Masked Deuce had a plan for the warships all along, leading them to a rocky reef area. Once one of the warships hits the rocky reef, it started to sink. Isuka quickly stops fighting and jumps into the water to save her shipwrecked crewmates, but after a while she grows weaker and is threatened by a large wave. However, Ace saves her life by throwing her a life preserver, and she is angry at his actions. From that day forth, she swore to chase down Ace. She would have numerous encounters with the Spade Pirates as a result.
While the mood is initially awkward, Isuka tells Deuce that the burn scar on her hand that he was staring at came from when pirates burned down her village when she was a child, during which her parents were killed. She had been saved from the fire by Lieutenant Commander Draw, who had since become a Vice Admiral. She now wants no children to go through the same experience as her.
She recommends that Ace quit being a Pirate, as she does not see him as evil. She even offered Ace the chance to become a Marine, but Ace does not like the idea of quitting piracy and jumps out of the gondola. Deuce wonders if Isuka will take him hostage to get Ace to come back, but she replies that Justice does not take hostages and that she is on holiday anyway.
Three days later, Isuka, accompanying Vice Admiral Draw, approached Ace and Deuce in a slum area, where the Pirates were giving food to some starving children. Isuka reveals a letter from the Five Elders offering Ace the chance to become one of the Seven Warlords of the Sea, but Ace refuses, saying he does not like the Warlord system. Draw smiles and reveals that he shares the same sentiment, but then starts attacking Ace, taking the opportunity to take him down now that he's decided that he will not be a Warlord.
Draw reveals flamethrowers attached under his arms, and prepares to fight Ace's fire with his own as he unleashes his weapons, causing the slum around them to light up. Ace is appalled and tries to save the children in the slums, but the fire is too strong. However, while Deuce occupies Draw, Ace and Isuka manage to save the children. Deuce removes Draw's fuel tank, and Ace punches the Vice Admiral in the face, but his punch does no damage. Draw grabs Ace by the neck and lifts him off the ground despite Ace's Logia power, using Busoshoku Haki which Ace was aware of. Draw prepares to kill Ace in the name of Justice, and Ace criticizes Draw's Justice, one that leads to him burning children. Draw reveals that he sees burning innocents as a necessary cost of taking down pirates, and this revelation shocks Isuka, who breaks down crying.
Ace's flames cause Draw's fuel tank to explode, injuring both of them. The two continue fighting, and Deuce knows that Ace can win despite Draw's abilities. Ace overwhelms Draw in combat, and Draw reveals that Ace is now using Busoshoku Haki, which Ace does not put much thought into. The two of them punch each other in the face at the same time, which ultimately defeats Draw. Deuce lends Ace a hand back to their ship, but Ace cannot leave Isuka behind in despair. He puts his hand forward and offers to let her come on his ship, where she can be a bounty hunter and pursue him while on the same ship as him. Isuka laughs in bewilderment at his request, saying pirates and bounty hunters do not shake hands. Ace tells her to get onboard his ship as it starts to leave Sabaody, but she stays behind, intending to continue her path as a Marine. She thanks Ace, calling him by his name rather than his epithet for the first time, and Ace is saddened to part ways with her.
- Isuka (イスカ) is the Japanese name of the red crossbill. According to a medieval legend, the crossbill gained its crossed bill by trying to free Jesus Christ from the cross by pulling out the nails, which caused blood to spurt out and stain the bird forever as a token of its efforts. This fits with Isuka being a righteous Marine and her epithet "Nailing". Oda's design notes for Isuka in One Piece Magazine Vol.3 include a sketch of the bird and a note mentioning the legend.
- Isuka shares some similarities to Smoker in terms of role, as a marine chasing after the pirate protagonist.
- Like Smoker and Luffy, Isuka and Ace clash several times on Grand Line as Isuka attempts to capture Ace.
- Ace saves Isuka from drowning despite the two being enemies, similar to Luffy ordering Zoro to save Smoker during the Arabasta Arc.
- However, while Luffy was unable to defeat Smoker due to the latter's Logia intangibility, the power dynamic is reversed with Ace and Isuka as Ace possesses the Logia-type Mera Mera no Mi.
- Isuka's history with Draw is similar to that of Flare and Cyrano from Oda's one-shot story Monsters.
- Oda's original concept art for Isuka seems to have contained the text "Ace's lover" (エースの恋人 Ēsu no koibito?). However, this is only visible in a small panel used in a Color Walk 9 Tiger advertisement in One Piece Magazine Vol.10. In the Color Walk itself, only the word "lover" (恋人 koibito?) is retained on the concept art, while the concept art published in One Piece Magazine Vol.3 and One Piece novel A lack the text entirely. It is unknown why this text has been partially or fully erased in various releases, though it may be a dropped plot concept that was erased in order to not confuse readers.