Perhaps Naruto tries to forgive Hinata in the fanfiction. Given his kind - hearted nature, he may see her regret and be willing to work through the issues. He might understand that people make mistakes and give her a chance to redeem herself, although it would be a difficult and painful process for him.
Naruto might be initially heartbroken. He is a character who values loyalty and love deeply. So, when he discovers Hinata's cheating, he could be in a state of shock and disbelief.
Another possibility is that Naruto becomes more guarded and distant. He has been betrayed, and this could make him hesitant to fully trust Hinata again. He may still have feelings for her because of their past, but the cheating incident makes him question everything about their relationship and he might keep her at arm's length while he sorts out his own feelings.
Chapter 318, "Transformed Li Xuanling, Reform, 9th-Class Viscount (Part 3)", is the clearest early answer because it turns Xia Hong's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Scout Colonel Liu Yuan of the Cloud Dragon Army Reconnaissance Camp,... and follows through with The Ninth-rank Viscounts, from low to high, are respectively....
Chapter 306, "Rebel Collaborators, Chaos and Opportunism, Long Mountain Changes Hands", is the clearest early answer because it turns Zhu Xing's situation into a concrete plot event. The chapter turns that into something concrete by moving from Go notify the leader, have him quickly bring the main forces back to... to His initial thought was that the trials Li Hu suffered would instead....
Chapter 317, "Wrapping Up the Migration, Great Xia's Flourishing Scene, Star-picking Hall (Part 4)", is the clearest early answer because it turns Li Xuanling's situation into a concrete plot event. Early on, Madam, Seniors, I'm truly sorry, the young one wasn't meant to.... By the end, Han Yue greets the two Ministers' Wives!" "Greet the Minister's....
Chapter 153, "Word Spreads, Director Sun Takes the Lead in Shipping the CP!", is the clearest early answer because it turns Director Sun's situation into a concrete plot event.
Chapter 332, "Chen Ying's New Discovery, Xia Yuning, Good News Abound", is the clearest early answer because it turns Iron Eagle Squad's situation into a concrete plot event. Early on, Snowy night, two kilometers north of Xia City, at the mountain wall.. By the end, Is the captain suggesting that the reason there was a Rodent Tide....
Chapter 331, "Zhu Shun, Huang Tianxi, the Third Cold Yuan Banquet of Great Xia, and Xia Yuzong", is the clearest early answer because it turns Great Xia's situation into a concrete plot event. It opens with Upon hearing the excited sound of his nephew running towards the... and closes on Compared to you, he's far behind!" Zhu Shun wasn't saying this to....
Chapter 129, "Spent Millions Only to Drive Traffic to Jiang Li?!", is the clearest early answer because it turns Chixia Village's situation into a concrete plot event. Early on, When they saw that the live chat was full of praise for Jiang Li,....
Chapter 158, "It's Time to Recruit Someone Who Understands Mysticism to Work Here", is the clearest early answer because it turns Sister Li's situation into a concrete plot event.
Chapter 148, "None are Normal", is the clearest early answer because it turns Su Yinwan's situation into a concrete plot event. The chapter gives readers a real answer by opening on Exiting the cottage, Director Sun picked up the phone.
Chapter 302, "Did You Just Stomp on the Answer Sheet Twice Before Handing It In?", is the clearest early answer because it turns Qu Theory's situation into a concrete plot event.