Over almost 30 years, One Piece has developed an incredible leading cast in the Straw Hat Pirates. Starting with series protagonist Luffy and going all the way to the latest member, Jimbei, every member of the Straw Hats has consistently proven themselves to be some of the strongest and all-around entertaining characters in all of One Piece, and those qualities only become more apparent with every new arc.
The Straw Hat Pirates make for an incredible ensemble in One Piece, but it could have been even better. Naturally, every arc in One Piece sees the Straw Hats bonding with new characters, and while some of those characters don’t have much presence beyond their initial arcs, plenty of characters in One Piece have been so great and played so well off the Straw Hat Pirates that it’s odd they never joined the crew. A few characters like that especially stand out, as if even one of them had joined the crew, One Piece’s story would have been even better.
10
Gin
First Appearance: One Piece Chapter 44 & Episode 21
Gin is the right-hand man to Don Krieg, one of the main antagonists of the East Blue saga. Gin bonded with Sanji after Sanji saved him from starvation, and while he was forced to fight Sanji as part of Krieg’s plan to steal the Baratie, he was too thankful to Sanji to go through with it and parted with Sanji on friendly terms as he headed back to the Grand Line.
Between his unique fighting style, his great chemistry with Luffy and Sanji, and a surprising amount of character development, Gin is a standout among early One Piece characters and someone many fans wish had joined the Straw Hat Pirates. One Piece chapter #1117 gave Gin a surprise cameo during Vegapunk’s speech, and while he’s unlikely to join the crew at this point, that still leaves room for him to at least reunite with Sanji at long last.
9
Nefertari Vivi
First Appearance: One Piece Chapter 103 & Episode 62
Nefertari Vivi is the princess of Alabasta who was introduced as Miss Wednesday, an agent of the criminal organization Baroque Works. Vivi infiltrated Baroque Works after discovering that they were behind the civil war in Alabasta, and after her cover is blown, the Straw Hats escort Vivi home to help her take down Baroque Works and put an end to the civil war.
Thanks in large part to how much time she spent in the story, Vivi is one of the characters with the deepest connection to the Straw Hat Pirates with the most developed personality to match, and decades later, many fans still lament that she stayed in Alabasta instead of going with the crew. In-universe, Vivi has always been treated as an honorary Straw Hat Pirate, and with Vivi returning in One Piece‘s final saga, she might finally join the crew for real.
8
Karoo
First Appearance: One Piece Chapter 109 & Episode 65
Karoo is Vivi’s pet super spot-billed duck, a species of duck native to Alabasta that can run at incredible speeds, who’s almost always by Vivi’s side. Naturally, that included when Vivi infiltrated Baroque Works, and when the Straw Hat Pirates escorted Vivi back to Alabasta, Karoo was right there with her every step of the way.
While Karoo’s character is largely dependent on Vivi, he still brings plenty of comedy to every scene he’s in, and just like Vivi, it would have been easy enough to have him join the Straw Hat Pirates at the end of the Alabasta arc. That being said, Karoo, like Vivi, is treated as an honorary member of the Straw Hat Pirates, in-universe, so with Vivi coming back into the spotlight, it probably won’t be long until they’re both officially part of the crew.
7
Mr. 2 Bon Clay
First Appearance: One Piece Chapter 129 & Episode 78
Mr. 2 Bon Clay is a former member of the criminal organization Baroque Works who bonded with the Straw Hat Pirates while they were unaware of each other’s identities. That bond led to Mr. 2 helping them escape Alabasta, and much later, Luffy reunited with Mr. 2 when he broke into Impel Down to save Ace, with him being Luffy’s biggest ally throughout the ordeal.
Not only does Mr. 2 provide plenty of great comedy and heart, but Mr. 2’s supporting role in One Piece’s Impel Down arc developed him into one of Luffy’s best allies thanks to how far he went to help him, and he remains one of One Piece’s most popular characters because of it. Mr. 2 left the story in a way that would make it difficult for him to join the Straw Hat Pirates, but that doesn’t make it any less of a missed opportunity.
6
Bellamy
First Appearance: One Piece Chapter 222 & Episode 146
Bellamy the Hyena is a character who was first introduced as a minor antagonist in the Jaya arc who antagonized Luffy until he was famously beaten in a single punch. Bellamy returned in the Dressrosa arc as a subordinate to Doflamingo, albeit a humbled man thanks to his time with Luffy, and the two developed a surprising friendship that led to Bellamy becoming one of Luffy’s biggest allies.
The way that Bellamy developed as a character was great to see, as was his surprisingly good chemistry with Luffy, but not only did Bellamy not join the crew, but he didn’t even join the Straw Hat Grand Fleet and retired from piracy, altogether. It makes sense for Bellamy’s character to do something like that, but it still would have been great to have him around in some way, regardless.
5
Carrot
First Appearance: One Piece Chapter 804 & Episode 753
Carrot is a rabbit mink the Straw Hat Pirates befriended when they visited Zou. When the crew split up so some would save Sanji from Big Mom while others went to Wano, Carrot snuck into Luffy’s group going to Whole Cake Island, and she played a major part in the story from then on out.
Between her fun personality, unique fighting style, and how well she played off the other characters, Carrot was someone many people hoped would join the Straw Hat Pirates, and her spending years with the crew made that a certainty in the minds of many. The way One Piece unceremoniously got rid of Carrot at the end of the Wano arc was a major sticking point for many, but hopefully, it at least won’t be the last appearance she makes in the story.
4
Vinsmoke Reiju
First Appearance: One Piece Chapter 826 & Episode 784
Vinsmoke Reiju is Sanji’s older sister and a member of the infamous mercenary force Germa 66. While Sanji’s brothers spent years torturing Sanji, Reiju was always nice whenever she had the chance, thanks to not being completely stripped of her emotions, and she was even the one who helped Sanji escape from their family into the East Blue as a child.
Despite her initial portrayal, Reiju quickly became a very sympathetic character and a great ally to Sanji, and with her not showing any particular love for her family, it would have made sense for her to leave them alongside Sanji and join the Straw Hat Pirates. Unfortunately, Whole Cake Island ultimately ended with Reiju staying with the Vinsmokes, and even with the recent cover story starring them, it’s unknown if she’ll ever have a large part to play in the story again.
3
Charlotte Pudding
First Appearance: One Piece Chapter 651 & Episode 571
Charlotte Pudding is a daughter of Big Mom who was set to marry Sanji as part of a ploy for the Big Mom Pirates to steal the Vinsmoke’s technology. Just as the plan was about to go underway, though, Sanji called Pudding’s third eye beautiful, something no one had ever done before, and she fell in love with Sanji for real and helped him and the Straw Hat Pirates escape Whole Cake Island.
Between having a power connected to One Piece’s wider lore, the abuse she’s suffered under Big Mom, and Pudding’s undeniable romantic chemistry with Sanji, Pudding joining the Straw Hat Pirates would have been great, but the story never capitalized on that. One Piece recently revealed that the Blackbeard Pirates have kidnapped Pudding after a raid on Whole Cake Island, so hopefully, that will lead to a reunion between Sanji and Pudding that formally solidifies their relationship.
2
Kozuki Momonosuke
First Appearance: One Piece Chapter 684 & Episode 609
Kozuki Momonosuke, often shortened to just “Momo”, is the son of Kozuki Oden, a legendary samurai killed by Kaido and Orochi in his attempt to save Wano. After a chance meeting on Punk Hazard, Luffy and the Straw Hat Pirates took it upon themselves to help Momo save Wano, and after doing so, Momo claimed his rightful place as the shogun of Wano.
While Momo becoming Wano’s shogun was a valid reason for him to leave the story, after spending a decade of real-time with the Straw Hat Pirates, Momo had essentially become a main character in his own right, and their separation was nothing but bittersweet. Nevertheless, Luffy considers Momo an honorary member of the Straw Hat Pirates and even made Wano his first official territory as an Emperor, so there’s still a chance he could join before the story’s over.
1
Yamato
First Appearance: One Piece Chapter 971 & Episode 972
Yamato is the son of Kaido who has spent his life idolizing Oden and openly defying Kaido because of it. Yamato also grew to idolize Luffy after hearing stories about him from Ace, and when Luffy led the raid on Onigashima, Yamato threw his lot in with the Ninja-Pirate-Mink-Samurai Alliance and played a major part in their ultimate victory.
Yamato expressed a desire to join the Straw Hat Pirates from the moment he was properly introduced, and his great fight scenes and character development made that great to look forward to, but surprisingly, One Piece’s Wano arc ended with Yamato staying on Wano to help Momo protect it from potential threats. One Piece can still add Yamato to the crew before the story ends, but the fact that they didn’t join already will always be a little weird.