Characters who won't return in one piece

The narrative structure of a piece Ensures many characters are placed in scenarios where they can return to the story, even after long absences. That being said, even with the opportunities this structure provides, there are a handful of characters we won't see much of, due to various circumstances. While the exact reasons behind each character vary, most of them are united only by the fact that the story seems to have left them behind, for better or worse, without an easy way back. These characters have likely already made their last, if not one of their final appearances in the series.

7 Nero

Probably dead

Niro was a member of Cypher Poll 9 (CP9) who only knew four of the six Rokushiki techniques, being uneducated in Tekkai and Shigan. Despite being a cut below most of his counterparts, he was able to hold Frankie for a while. However, his own relative inexperience had him expelled after repeated failures. He was wounded by Rob Lucci and thrown into the sea in a storm known as Aqua Laguna.

There has yet to be any official confirmation that Nero died, leaving open the slim possibility that he somehow survived the storm. Even if that were the case, it still wouldn't translate into more appearances. This is because Nero is fundamentally too insignificant of a character to be declared dead. Perhaps he might reunite at the end of the series with other characters who haven't been killed off, but given his amoral nature, possible death, and relative importance, there's little to bring him back to the series.

6 Hodie Jones

Aging rapidly

Hody Jones is the first serious villain in the post-timeskip era a piece. He is the captain of the new Fish-Man Pirates, and a blind follower of Arlong's ideals, knowing nothing of the people he claims to hate so deeply. He attempts to take over Fish-Man Island by force, which he will use as a springboard to formulate a vague plan to take over the world. Yet for all his talk, he and his crew proved unable to take on Fish-Man Island's top-ranking soldiers without some form of support.

For this purpose, they constantly consume energy steroids, which will temporarily increase their physical strength. Although this led to premature aging, it gave them more strength. However, these steroids not only prevented their defeat, but eventually aged them beyond the point where they could fight. Hoddy in particular took the most steroids, and seemed to be in more pain than his peers. They were all imprisoned for their crimes.

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Given the fact of their rapid aging and the larger story's less focus on fish-man supremacist groups, there seems little reason to return Hoddy and his crew properly.

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3 Anel

Man in the Moon

For all the important lore revealed during the Scipia arc, one cannot ignore that it takes place in a completely different terrain than the established blue seas seen during most of the story. This fact can be seen through the characters who have little investment in the action below, one of whom is Enel. This self-proclaimed “god” seems largely satisfied with his acquisitions, only to be disappointed by his inability to discover Fairy Worth, the legend told by the Birkan people.

After his defeat against Luffy and more importantly, the loss of his power on Skypiea, he refocused his efforts on finding the Fairy Worth. It turns out, it was, in fact, the moon. Enel eventually encountered the Automata on the moon, who were there to avenge their creator, who died due to an explosion on the moon. Upset said that the aliens were insulting Faerie Worth, so he took them out himself. After using his electrical powers to resurrect the defeated automata, he discovers their army underground, as well as evidence linking the sky-dwelling races, and decides to rule the moon.

When one considers his complacency with this goal and the apparent lack of people negatively affected by it, Enel is unlikely to return, unless his lunar base somehow comes into play.

2 joju

In hiding

Joju was a key member of the Whitebeard Pirates, one of its 16 division commanders (specifically leading the 3rd Division) his Devil Fruit allowed him to transform his body into a nearly indestructible diamond at the cost of mobility. Properly placed he can prevent even the powerful slashes of Dracul Mihawk, the strongest swordsman in the world, from doing any damage.

However, the deaths of their captain, Whitebeard, and crewmate, Ace, during the Battle of the Summit seemed to spell the end of the Whitebeard Pirates. This was expanded upon during the Payback War, where the remnants of the crew perished with the Blackbird Pirates. Since then they have been in hiding, the whereabouts of most of the members is currently unclear.

It's not impossible Joju could return, especially if more attention is focused on what happened to the other surviving crew members, but there seems to be little opening for that right now. For now, it can be assumed that she is hiding, although exactly where is unclear.

1 Gaimon

Protecting the island of rare animals

Gaimon is the man who fell into a treasure chest, and is supposed to a piece A favorite character of the author, Eiichiro Oda. This fact, along with his hair which grew back, gave him a strange but charming appearance. He charmed Luffy to the point where the captain requested that he join the Straw Hat Pirates. Gammon refuses, feeling an obligation to protect the rare animals on the island and to be involved.

He has since developed a relationship with the future emperor, Buggy, when he himself was briefly on the island. A seemingly more permanent resident is Sarfunkel, a woman trapped in a barrel similar to her plight. The two appear to be romantically involved, as her love feeds on him. The pair were two of many who listened to Vegapunk's message, but this would likely be their last appearance. Factors limiting Gammon's involvement include his limited relevance and low combat capability, in addition to his desire to remain on the island.