In the most recent chapter of One Piece, a character has made an unexpected return. Having not been seen since before the raid, Kozuki Hiyori -- in her Komurasaki disguise -- has seemingly made her way to Onigashima Island at some point during the raid, unbeknownst to anyone. Even more surprisingly, the only person that she's chosen to reveal her presence to is none other than Kurozumi Orochi.
Since the start of Wano, Hiyori has played a central role in the unfolding of the arc's story. After surviving Orochi's attempt to kill her and the rest of the Kozuki family thanks to the efforts of Kawamatsu, she was later taken in by a man named Kyoshiro, who was secretly Denjiro in disguise. While under Denjiro's care, she became a spy who acted as a consort to Orochi named Komurasaki and quickly became his favorite. "Komurasaki" was later killed by "Kyoshiro" in order to save her from the clutches of Orochi, allowing her to escape him for good.
Since then, Hiyori has been aiding the rebel forces against Orochi and Kaido, most notably providing Roronoa Zoro the sword Enma to replace Shisui. So far, this seemingly small act has given the rebel alliance a huge advantage against Kaido, as Zoro managed to do the impossible and scar Kaido in an intense battle. In this sense, her role has been significant, yet also quite small and indirect -- until the most recent chapter, at least.
Making a surprise appearance as Komurasaki once again, Hiyori has somehow managed to make it to the island, specifically to where Orochi is hiding, although her purpose is unclear. However, it can be reasonably ascertained that she is the mysterious individual who helped heal the scabbards after their fight with Kaido, especially because her jewelry matches those from the silhouetted figure.
Unfortunately, why she has gone to Orochi or even how she made it to the island to begin with are still complete mysteries. Given what readers and watchers have seen, it's obvious that if this figure was indeed Hiyori, it would all be a ploy on her part to try and trick the despicable shogun. Even with that said, it's quite a surprise to see Hiyori there at all, especially as she refused to see her brother whatsoever until the raid was over.
Another thing to keep in mind is that this woman might not actually be Hiyori, but rather her mother Toki. In One Piece, it's not uncommon for characters to look a lot like their parents or ancestors. As seen in the flashback, Toki and Hiyori both look startlingly similar, with very few distinctions between the two. The only visual difference between them that could be told through a black-and-white manga panel is that Toki has a scar on her leg. This might be nothing more than a coincidence, but the panel that reveals Komurasaki isn't drawn in a way that gives readers a good look at her leg.
Given her unique Devil Fruit, it's also possible that Toki traveled to the future just before her death in order to be on Wano to fulfill her own prophecy. Since her introduction, Toki has always been a bit of a mystery. As someone who was alive during the Void Century, she knows more about the secret history of the world than just about anyone, and she seems to have a strange connection to Wano and its future.
Strangely enough, when first meeting Oden, she made it quite clear that she wanted to go to Wano. Then, when they arrived, she was unable to go to Laugh Tale with him and the Roger Pirates and wouldn't let Oden stay with her. Many fans theorize that she knew what would happen to Wano after he left, knowing that Oden would be the only one capable of stopping Kaido and Orochi from gaining control of the island. There are even panels that imply she knew that Momonosuke would need to lead Wano in the future.
The greatest possible hints that this individual is really Toki comes from the night of her death. Not only does she only send a specific and particularly small group of Oden's vassals into the future, but she also didn't send her daughter with them even though she could have. She then has different vassals keep Hiyori safe in the present while she makes a grand declaration to Orochi about his demise in 20 years, completely ruining any chance of a sneak attack. Toki definitely knew more than she let on, and it's very possible that the person Orochi sees on Onigashima is really her.
As things stand, there are a lot of things happening currently during the raid -- so many that even this revelation isn't the most important event occurring at the moment. It's clear that whoever is using the Komurasaki mantle is an important player in the story moving forward, but how they will affect the story is still a total mystery. Fans will have to hope that series creator Eiichiro Oda will grace them with answers sooner rather than later.