I have't been giving enough posts to the One Piece fandom side of this account. While the Twitter ones need to be re-formatted, fixed for typos and other edits. Here is one I did on Discord a while back for all my fellow LuVi shippers <3
Reasons to see LuVi as endgame
Luffy's words to Crocodile about her, and their fight. Luffy states Vivi's qualities to Crocodile when defending her, recognizing her strengths and what she cares about.
Then, when Luffy and Vivi punch each other in their fight over what to do about Alabasta, Luffy marks Vivi as an equal. He does not do this to any of the other princesses in later arcs, seeing them more as damsels.
While he listens to the stories of Rebecca, Shirahoshi, and Hiyori (or would it be Yamato? Not sure for the princess/damsel of Wano.) He defends them, and fights for them, but he never fights them themselves like an equal. Just someone he has to protect.
For Vivi he fought her to fight for her, and saw her on the same playing field. Plus the specific qualities and his 'Luffy in thought scenes,' in Alabasta just showed he really cared for her.
Little Garden: Luffy wants to adventure, with his usual spirit and excitement. Nami doesn't want to, yett Vivi asks to join. This shows that they share a thrill for adventure as kindrred spirits. While Nami and Sanji stay behind/more hold the fort. It also shows, Vivi can keep up with Luffy and compliment him.
Drum: Vivi taught Luffy to be a better Leader with diplomacy, giving the lesson to not always impulsively fight first. It's only after seeing Vivi bleeding does Luffy take this lesson to heart and bow. -- This same lesson of leadership and bowing to an enemy, comes up again when Luffy is before Hancock to soften her heart and ultimate lead to her helping him. On the flipside, Luffy doesn't tend to like to listen to anyone unless they force it into him (i.e Zoro), but he did Vivi.
When Vivi is mentioned, Luffy acts more interested. Like when Nami was reading the paper about Sabo, Luffy only seemed to listen nonchantly until Vivi ws brought up. Then, he was immediately set on dropping everything, turning around, and going to help her before Zoro talked him out of it. On the flipside in Egghead, Robin mentioned Sanji saving Nami if she screamed, and Zoro noted she scream, but Luffy didn't say or do anything (Toei pushed and added a scene of him screaming Nami, that wasn't in the chapter.) So he's quick to drop everything for Vivi, but knows Nami is already in good hands.
Vivi as well is always keeping up with the crew and watching them in the news whenever she can. Constantly asking about Luffy and knowing how he thinks
The only time Luffy has peeped with the rest of the boys, is when Vivi was also there. Other times he's not interested. Oda said this was because of Usopp bringing out Luffy's naughty side, but it's interesting Vivi was there not just Nami. Other times, he has no reaction like with Boa.
Cobra basically gave his daughter away to Luffy. We had panels of him talking about suitors, and Vivi telling him to toss them while winking, implying she may already have someone in mind. When Cobra died and told Sabo to tell Luffy and Vivi they're D's too, he did it in a way that he entrusted his daughter to Luffy, in traditionalism that's seen as giving the daughter away.
Parallels. Not only are we getting Lily the ancestor and Joyboy talk now. Vivi is also revealed to be a D, paralleling her with Rouge like Luffy is paralleled to Roger. To add to it. Oda said Luffy's color is RED. (Rouge) and Vivi's color is White and GOLD (he specifically added the gold.) (Roger) making the two a reverse of Roger and Rouge in color language, and both being Ds like the two.
Even Luffy's VA, Mayumi Tanaka said she believed Luffy had feelings for Vivi when asked about Luffy and Nami.
The only time Oda's mentioned a Pirate Queen (funny enough Big Mom as a woman wanted to be Pirate KING) was in Igaram's dream of Vivi running off. Other than that, we have Pirate King, Pirate Empress. But no Pirate Queen title. And then Oda did this Art as well.
And in the artwork, Luffy and Vivi are wearing each other's signature colors: Luffy in White and Gold, and Vivi in shades of red.
When Oda gave Vivi's crew information, he marked her crew number as 5.5, Luffy's Birthday which falls on May 5th.
This one is slightly reaching, but authors have patterns. And a big pattern for Oda has been to always make the man older than the woman in his official couples. Other than Big Mom's multiple flings, Gaban and the giantess and Jarul's mention of liking older woman which were all pointed out in-story -- he never strays from this pattern. Even Usopp is a few months older than Kaya.
Luffy with Vivi follows this as he is older than Vivi, but younger than Nami (Sanji is older than Nami though <3).
And now, even the Live Action gave us LuVi scenes while putting Nami with Sanji.
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And last, this more of a tinfoil hat reaching: Oda has Vivi wear a Tiger t-shirt in a color spread, and her ancestors is Lily. He's also linked the D clan with Tigers in other covers, and color spreads and even in the manga like Clover who also turned out to be a D's robe showed.
Oda has referenced and paid homage to Peter Pan in Thriller Bark with Moria and the shadows, and in other times as well. And in Peter Pan, Tiger Lily was the chiefs daughter who had a crush on Peter. But that's more going down the rabbit hole.