Naruto: Momoshiki Is Basically Boruto's Nine-Tails

Boruto: Naruto Next Generations threw a twist into the series early on, after Boruto destroyed Momoshiki Otsutsuki. The villain's "death" left Boruto marked with the mysterious Karma seal, which began to reveal unusual abilities of its own. Momoshiki left Boruto with a dark proclamation along with his mark, warning him that his special blue eye (the Jogan) would cost him everything. (Manga Spoilers) That prophecy has started to come true in Boruto's latest manga arc, as the battle with a new Otsutuki threat (Isshiki) has confirmed that Momoshiki is slowly but surely taking over Boruto's body. In that sense, Momoshiki has basically become Boruto's Nine-Tails.

The story of Naruto Uzumaki centered around the young would-be shinobi being an orphan outcast saddled with a very dark burden. By having the savage and apocalyptic Nine-Tails beast sealed inside of him, Naruto was often viewed with the same disdain and revulsion as the monster he carried. The fear wasn't without merit: the times when Naruto lost control over Nine-Tails were truly life-threatening to his family and friends. Naruto learning to make peace with the beast inside and embrace who he is was as important to the saga as any Shinobi War.

Boruto isn't going to be as fortunate. Kurama was an angry mythical beast with a chip on his shoulder - but that's leagues away from a nefarious and sadistic evil alien parasite. Kurama ws looking for a way out of his cage; Momoshiki is very much trying to get into Boruto and take his body over. His evil goals don't end there - Momoshiki wants to feed Boruto's new brother-in-arms Kawaki to a Ten-Tails, in order to grow the Divine Tree that will suck Earth's chakra dry. That's a much more ambitious goal than raging out at humanity like Kurama wanted to.

At the same time, the difference in context between the internal burden Naruto and Boruto each have to carry is what's going to arguably make the Boruto series more interesting, going forward. Having an evil killer alien talking in his head gives Boruto a Venom-like quality that will be fun to follow.

The threat of Momoshiki will also be ever-present in a way Kurama wasn't, as Boruto will be a very real threat to everyone around him - especially his teammates in battle. If Boruto loses too much chakra, Momoshiki takes over - and the villain has already crippled Sasuke with his first surprise attack.

Momoshiki's presence will also hopefully force Boruto into a new life POV. Instead of being the bratty son of a celebrity ninja, Boruto may have to experience more of the isolation and loneliness that Naruto did as a youth. Maybe that will help explain the somber and serious Teenage Boruto we met in the series' opening flash-forward.