While Naruto has its fair share of brutal scenes, Shonen Jump's Chainsaw Man takes many of that beloved series' elements and pushes them into a much gorier place.
Due to cultural differences between America and Japan, there are many things in Naruto that some in the west would be shocked to find in a series aimed primarily at young adults. Raunchy humor, brutal deaths, and frequent references to alcohol are all quite common in the ninja world. One of the first jutsu Naruto uses in the series turns him into a naked lady. Even though this, and many other elements of the series, raised many an eyebrow from localizers when the series was brought to the west, all of it is consistently juvenile. There is raunchy humor, yes, but there is very little in the way of actual intimacy. There is violence, yes, but even when the violence has lasting consequences it is so detached from real-world violence that it's hard to relate to. None of this is meant as a criticism of Naruto. These elements helped Naruto communicate its story to its teenage fanbase in a way that more realistic or adult elements wouldn't. Now though, much of that original base has grown up, and any former fan of Naruto looking for a more grownup experience needs to read Chainsaw Man.
Chainsaw Man by Tatsuki Fujimoto shares many surface similarities with Naruto. Its protagonist, Denji, is a blond social outcast with a demon sealed inside of him that makes him an absolute nightmare to face on the battlefield. His chief rival, Hayakawa, is a disciplined fighter with black hair who uses a sword, has a special power based on his eye, and is willing to sacrifice anything to get revenge for the murder of his entire family. Though the obvious parallels to Naruto are almost certainly unintentional, they do provide an interesting contrast. Whereas Naruto's interest in women is goofy and played for comedy, Denji's similarly juvenile desires are used as tools to manipulate him. Where Naruto befriends Kurama, bonding with Pochita strips away Denji's humanity. Denji shows an alternate, much more depressing, path Naruto could have taken if his morals weren't so firm.
One of the reasons Naruto accomplishes everything he does throughout his series is that his isolation as a child gave him a sense of empathy that allows him to emotionally understand the pain his villains face. Though Naruto is probably the most famous example of this in shonen manga, he's far from the only hero like this. One of Chainsaw Man's biggest tricks is flipping that trope on its head. Denji's terrible childhood didn't make him stronger, it made him easy to manipulate. Naruto's isolation doesn't compare to what Denji faces in Chainsaw Man. Throughout the manga, multiple characters refer to Denji as a dog, and it's a fitting moniker because all of his motivation centers around base needs. Whether it's an offer of food, shelter, or gratification, it doesn't take much to motivate Denji. While Naruto has his goal of becoming Hokage and is always driven by his morals, Denji never had time to want anything other than physical and emotional safety.
Ultimately, any similarity between Naruto and Chainsaw Man is probably accidental, as Fujimoto hasn't listed the world-famous manga series among his influences. Still, the similarities are striking when put side-by-side. Any fan who grew up with Naruto and was looking for something a lot bloodier and much more mature should give Shonen Jump's Chainsaw Man a read.