Eiichiro Oda’s One Piece and Hiro Mashima’s Fairy Tail are filled to the brim with exciting, interesting and developed female characters. The two shonen series are primarily aimed toward a male audience, following the traditional structure of a prime male protagonist with secondary female character supports. However, due to the sheer multitude of characters within both series, there are numerous situations where the ladies steal the spotlight and progress the narrative. This goes for both the heroes and the villains. It could be argued that female representation in these two series outshines some of their fellow shonen titles, such as Bleach and Naruto.
However, they do not come without criticisms. One Piece and Fairy Tail have been known to tread the line of oversexualized scenarios that, at times, become more of a focus in the episode or chapter than the actual substance of the plot. While some are fleeting, others become a staple of a character's combat. When comparing the two series in their representation and development of female characters, there are some obvious similarities and stark differences, questions about the artwork decisions, but also some of the greatest female characters brought into the manga world.
When considering the female characters' roles in One Piece, it is safe to say they are present and powerful in the aspect of piracy. One of the strongest pirates in the series is Charlotte Linlin, holding a bounty of 4,380,000,000 berries. As the highest female bounty in the story, she only sits below Gol D. Roger, Whitebeard and Kaido. However, she sits alone on the podium of absurdly powerful characters, with no other female yet being comparable with her strength.
There are no female characters in the Navy who can wield the strength of an Admiral. It is possible that Tashigi, who is currently ranked Captain, would one day rise to be a threat to Zoro’s position of the strongest swordsman, but unfortunately One Piece has yet to give this theory a foundation due to the lack of her progression in strength, as shown in Punk Hazard. All in all, with the dissolving of the Shichibukai and loss of Boa Hancock, the World Government is severely lacking in female representation -- unless there is something readers have yet to learn about the mysterious Im.
On the other hand, Fairy Tail boasts a number of powerful female wizards. Irene Belserion is a wizard with a potentially limitless pool of magic as well as the creator of Dragon Slayer Magic. She is considered the strongest female in the Spriggan 12, with only August ranking higher, and her performance in the "Alvarez Empire" arc proved that power. It was her love for her daughter, Ezra Scarlet, that turned out to be Irene's downfall in their battle, otherwise it was likely she would have been victorious against one of the story's strongest heroes.
There is also the formerly villainous turned hero Ultear, with her magical ability of time manipulation and repeated clutch moments throughout. Her power saves the heroes on more than one occasion, changing the very timeline of battles to turn the tide of a conflict. Granted, the power differences between Fairy Tail characters and the higher echelon of One Piece characters is vastly different; Fairy Tail tends to place a sharper focus on its female characters' battles and power.
The Straw Hat Crew have two of the most developed characters in One Piece: Nami and Nico Robin. Nami started out as an untrusting trickster, known for her thievery and abandonment of those she vowed to assist. The change of her character came rather quickly once she was officially established into the crew at Cocoyasi Village, during the confrontation with the Arlong. Though, this was not the end of her development. Nami became the glue that kept the Straw Hats together, the voice of reason and a true believer in the dream of her captain, Monkey D. Luffy, refusing to bend to Ulti’s intimidation even with the prospect of death looming over her. Tearful and terrified, her resolve was on par with the likes of Luffy, Zoro and Sanji.
Nico Robin’s journey was a road of pain, heartbreak and fear, doing whatever she needed to survive. She never truly trusted anyone and used those around her to benefit her goal of learning the truth of the Void Century. One of the most memorable moments in the entire series came during the challenge against CP9 at Enies Lobby, where Nico Robin proclaimed her desire to live and sail with her newly formed family. In a sense, her character embraced the idea of close bonds; the structure of her life up to that point was discarded for the hope of a better future. This development did not come at Enies Lobby, but was built up during her adventures with the Straw Hats on Skypiea and the beginning of Water 7, as she slowly understood the self-sacrifice the rest of the crew would make to protect those they called friends.
Ezra Scarlet was introduced as an S-Class wizard the Fairy Tail guild, in the same company as Laxus Dreyar, Gildarts Clive and Mirajane Strauss. Her personality throughout the story is the supporting big sister to the main cast, who would do anything in her power to keep them safe. Much of her development coincides with Jellal Fernandes and their relationship.
Their dynamic shifts considerably from foe to friend to desired lovers. Yet, Erza's progression in terms worldview or personality is slim -- as fantastic as her character is, it remains rather static. Lucy Heartfilia is the Fairy Tail's narrator -- even if it is still mainly Natsu's journey -- and shares the spotlight more than any other character in the series. Her personality only makes small changes over time, though her reliability and resolve follows the trend of Nami, becoming Natsu's closest and greatest ally in the constant obstacles the Fairy Tail Guild faces.
On the flip side, Wendy Marvell joins the cast as a shy and quiet character, unable to apply her true potential to battle or situations due to a lack of self-confidence. As the story progresses, so does her confidence. Through constant trials where she could not always rely on someone else to use her support magic on, Wendy unlocked the true power inside her and learned that being able to stand alone against evil is part of being in Fairy Tail.
Juvia Locksar has quite the wholesome growth; initially an emotionless weapon in the Phantom Lord Guild, she evolves into a joyful and hopeless romantic after joining Fairy Tail. Her emotional development and increased devotion to her guild mates mirrors the growth of Nico Robin, learning to accept what real friendship means.
A critique of both these shonen juggernauts is the way female characters are depicted in regard to fan-service or artistic style. While One Piece has its moments of fan-service -- such as Nami’s ninja uniform in Wano or Sanji’s obsession with the scantly dressed mermaids in Fishman Island -- they pale in comparison to the repeated loss or tearing of female clothing in Fairy Tail.
The drawn perspective for some fights containing female characters is arguably purposely chosen to reveal as much flesh as possible, and the magic attacks they suffer tend to shred more attire than that of their male counterparts. That is, except Gray Fullbuster and his love for stripping down in a fight. One Piece has an art style in which its female characters share the same features and body types, making many appear very similar. It's only when female characters hit a certain older age that their appearance shifts dramatically to a more unique style.
When it came to female character development, One Piece takes the medal here. However, in art style and fan service, both series suffer with routine depictions that could be considered questionable. In terms of strength, while One Piece has an immensely powerful character and Fairy Tail portrays a good few, they are mostly overshadowed by their male counterparts -- a common occurrence in shonen. The female characters in both series are wonderfully written, developed and integral to their respective plots, but if one were to beat the other with justice given to their representation, One Piece stands above the magical manga.