WARNING: The following contains major spoilers for Boruto: Naruto Next Generations #44, by Masashi Kishimoto, Mikio Ikemoto and Ukyo Kodachi, available in English from Viz Media.
Boruto #44 has shaken things up in a big way for Naruto and the Land of Fire known as Konoha. Considered the main village in the free shinobi world, they've been leading the charge against Jigen's terrorist cell, Kara, however, they've not seen much success. Still, little victories count, and rescuing Naruto from Boro and also getting Kawaki back safe and sound matters a lot in the war to come.
But things may not be on the upswing as much as we think, with Sasuke now in a quandary having learned Boruto's deep, dark secret -- one that could doom everything Sasuke and Naruto built over the years.
Sasuke's recovered from his injuries after fighting Kara and is reacquainting himself with Boruto and Team 7 after their rescue mission. They brought Naruto back but barely survived the brawl against Boro, and Sasuke wants to know what went down. His daughter, Sarada, and Mitsuki hold nothing back -- and reveal how Boruto turned into some kind of alien in his battle, killing Boro. When they describe the horned transformation Sasuke immediately pieces it together and realizes Boruto is a vessel for an Ōtsutsuki as well.
He saw it with Jigen when the villain tended to the Ten-Tails and now, after conferring with the young ninjas, he can tell Boruto's Karma mark is what allows this. The meeting jogs Sarada's memory and she recalls their fights with Momoshiki and Kinshiki Ōtsutsuki, so she knows her father's hunch is right. Boro wasn't teasing when he let the secret slip too. Momoshiki has been tempting Boruto and his spirit seems to reside inside the boy, so Sasuke believes it's a matter of time before he finishes the possession and attempts to be reborn in Boruto's body.
He knows what it's like, having been marked by Orochimaru with a Cursed Seal like this in the past, but he's even more worried this time as Boruto already has chakra, as well as the potential inside of him to be even greater than his dad. If Momoshiki succeeds, he could become even more powerful than Jigen, Naruto or Sasuke. The ranger's problems don't end there, though, because he also knows Kawaki is also a vessel for Jigen, who in turn is a vessel for Isshiki Ōtsutsuki. So pretty soon, Konoha could have a couple of unstoppable tyrants knocking on its doorsteps.
Sasuke's clearly very concerned, although he stops short of showing how truly petrified he is. All he can do right now is hope Kawaki and Boruto don't manifest, and that Naruto heals as fast as possible. With Amado coming over with Kara's secrets, he might get some insight into saving the kids, as well as on how to take Jigen down -- but Sasuke simply can't afford to blindly trust outsiders: He has to figure this out using his fellow Konoha warriors.
Despite masking his true feelings, Sarada can already tell her father is not optimistic about what's unraveling around him, especially as there are mysterious Kara soldiers like Code still out there, along with the deadly Ten-Tails.