WARNING: The following contains spoilers for Chapter #55, “Legacy,” of Boruto: Naruto Next Generations by Masashi Kishimoto, Mikio Ikemoto, Mari Morimoto and Snir Aharon, now available in English from Viz Media.
Despite initially positioning Kawaki as a villain that wrecked the Hidden Leaf village, the Boruto series has changed things up drastically since his adoption by Naruto and Konoha. He's now a brother to Boruto and someone who genuinely wants to look out for the Hokage, leaving many confused as to how he goes on to break bad in the future -- especially now that his oppressor, Isshiki, is gone.
Interestingly, while the manga has quite a ways to go before revealing the truth behind all this, it does manage to subvert a major aspect of Naruto and Sasuke's old rivalry in the latest chapter -- further adding to the mystery of Kawaki's eventual heel turn.
At the end of Chapter #55, Kawaki makes it clear to Boruto that no matter what, he will stick by his side. He'll do whatever it takes to get rid of Momoshiki's essence that's poisoning Boruto and cure him. This basically makes Kawaki a total good guy, completely flipping what we expected him to be. Sure, he's brooding, angsty and really disliked Boruto early on, and seeing as he had a curse mark, it did feel like he was the new Sasuke -- but, while Kawaki's like Sasuke, he's seems primed to fill the exact opposite role.
Chapter #55 seemingly marks the surprising shift of Kawaki into the relentless hero, which is the role Naruto occupied at his age. Naruto was always adamant he'd save and heal Sasuke, no matter what. And, as Kawaki wants to protect Boruto now, he's more or less become Boruto's Naruto, against all expectations.
It totally flips the script, as many assumed that Boruto would be the new Naruto, especially as he has the same childish attitude his dad did back then. But instead, he's turned into the Sasuke of this era, struggling with a dark power within. Granted, he doesn't rebuff Kawaki's help, he's grateful for it, which isn't what Sasuke did with Naruto.
Boruto feels reassured as Kawaki, despite losing his mark, promises he'll do whatever it takes to get rid of Boruto's as well. But hearing Kawaki say he won't rest and letting Boruto know it's a journey they'll take together is definitely reminiscent of the speeches Naruto gave Sasuke to remind him there was always hope.
It's quite fitting that Naruto and Sasuke are there with them, seeing the reflection of what they used to be. Which makes it even more intriguing knowing Kawaki will turn on them too, admittedly something Sasuke tried to do when the Kaguya War ended. Naruto beat sense into him back then, so it remains to be seen what will cause this rift and let that Naruto-like fire in Kawaki burn out.