It could be an evil spirit that has possessed Akeno. This spirit might be using her to get to Naruto because it sees Naruto as a threat to its plans, whatever they may be. So the main antagonist would actually be this hidden spirit.
If the fanfiction is set in a different timeline or universe, it could be that Akeno herself is corrupted by a dark power source. In this case, Akeno would be the main antagonist in a sense, but the real source of the problem could be the dark power that has changed her and made her want to hurt Naruto.
Chapter 448, ", Stealing a Boat is That Simple", is the clearest early answer because it turns Interstellar Warriors's situation into a concrete plot event. The setup is Wraith Spire scored a victory right from the start, one cannon blast..., but the pressure keeps building through That was the expected performance of a Retribution-class Battleship..
Chapter 389, ", Capturing the Planet", is the clearest early answer because it turns Wang Zhongze's situation into a concrete plot event. It opens with Every officer present was required to lead a battalion personally to... and closes on But even so, the quality of our troops is still a notch below those....
Chapter 417, ", All Forces Attack!", is the clearest early answer because the buildup finally cashes out in a real clash. The chapter gives readers a real answer by opening on Hearing this veiled refusal, Gu Hang's expression remained unchanged. and ending on For Gu Hang, winning the war came before everything else..
Chapter 443, ", the mobilization ratio must be higher!", is the clearest early answer because it turns Saru's situation into a concrete plot event. Early on, No.2 was already gone, No.4's pitiful state could be ignored for now,.... By the end, I will divert one hundred warships to return, picking up scattered....
Chapter 50, "Discussions And Differences I", is the clearest early answer because it turns Great Elder's situation into a concrete plot event. The setup is Within the main hall where the meeting wasto hold., but the pressure keeps building through Over seventy individuals were present, all of them standing in front.... Once the chapter lands on The cause for the speed up in the Bloodied Sky Transformation is..., the chapter closes with "Ah, also.
Chapter 458, ", You Dare Too?", is the clearest early answer because it turns Alliance's situation into a concrete plot event. The setup is This man was the second largest landowner on Eagle Horse III, a..., but the pressure keeps building through Ulrich knocked on the table, "Everybody stop, just stop!" Once the....
Chapter 111, "The Orchid Quest I", is the clearest early answer because it turns Damien's situation into a concrete plot event. The chapter turns that into something concrete by moving from The forest of Twin Disasters buzzed with life, the air thick with the... to Fenrir growled in response, his body lowering into an attack stance,....
Chapter 14, "Nonstop Growth", is the clearest early answer because it turns Damien's situation into a concrete plot event. Early on, Damien stood in place, essence cores in both hands.. By the end, Essence devouring was his new best thing and he needed to continue.. Inside the broader technology upgrade storyline, the chapter closes with The forest was filled with resources that aided non stop growth for Damien and Luton.
Chapter 441, ", Must Not Let Down the Heroes!", is the clearest early answer because it turns Zhang Zhikai's situation into a concrete plot event. The chapter turns that into something concrete by moving from They could no longer hold on. to Our mission has failed, but I'm not foolish..
Chapter 391, ", Mr. Gu", is the clearest early answer because it turns Gu Hang's situation into a concrete plot event. A useful checkpoint is the way the scene starts with During the call with Lois, the lady was quite surprised. and follows through with Applying the Alliance's rank system forcibly would set ranks for the....