Often in these fanfictions, their backstory of meeting could be related to the mafia world as well. Tsuna, as part of the Vongola family, might be on a mission near Hibari's territory. Hibari, being protective of his area, confronts Tsuna at first. But then they realize they have a common goal of protecting the innocent. This encounter could be the start of their relationship that eventually leads to marriage.
In some Tsuna and Hibari married fanfictions, they could meet during a school event at Namimori High. Maybe there was a threat to the school, and Tsuna's leadership skills emerged while Hibari was already in the midst of fighting the intruders. Tsuna might have calmed Hibari down and from that moment, their relationship started to develop.
Chapter 339, "The Changes in Li Hu and Yang Zhong, the Hou Family's Opportunity, and Advice (Part 2)", is the clearest early answer because it turns Yang Zhong's situation into a concrete plot event. The chapter turns that into something concrete by moving from According to the balance of their Contribution Value, it is actually... to Considering your high Martial Arts Talent, it should be Battle Body....
Chapter 8, "Is He Shameless?", is the clearest early answer because it turns Lin Manru's situation into a concrete plot event. The chapter gives readers a real answer by opening on The resentment that had barely calmed among the crowd surged back two...
Chapter 221, "No Choice, He Gave Way Too Much", is the clearest early answer because it turns Hua University's situation into a concrete plot event. Early on, Many agricultural students found themselves with tears brimming in....
Chapter 340, "Seclusion, Growing Yu Generation, Family Banquet, Rapid Development (Part 5)", is the clearest early answer because it turns Great Xia's situation into a concrete plot event. The chapter turns that into something concrete by moving from I haven't paid attention to the camp's situation for a whole year. to Over the past year, Xu Ning has not rushed things and has slowly....
Chapter 338, "Rapid Progress, Martial Arts Skills, Dual Advance Eastward, Dormancy Period", is the clearest early answer because Xia Hong finally turns buildup into a real advancement. Early on, Lu Yang poured out everything he knew in one breath.. By the end, If we continue exploring east along the Xing River North Bank,....
Chapter 221, "No Choice, He Gave Way Too Much", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Many agricultural students found themselves with tears brimming in...
Chapter 386, "New "Game" Mode", is the clearest early answer because it turns Du Sang's situation into a concrete plot event. Early on, Seeing Shang Shaojing's somewhat pale face, Su Yinwan's heart felt a.... By the end, After a long time, he finally spoke..
Chapter 24, "The Cause of Jiang Shixu's Illness", is the clearest early answer because it turns Shi Xu's situation into a concrete plot event. Early on, Not only that, even the non-mainstream photos she had previously....
Chapter 315, "New Policies for Long Mountain, Cold Apple Tree and the Silver Mine", is the clearest early answer because it turns Li Xuanling's situation into a concrete plot event. The chapter turns that into something concrete by moving from Only the third child, Li Xuandu, was ten years older than her and... to Based on what those two just said, if I chased after them and killed....
Chapter 339, "The Changes of Li Hu and Yang Zhong, the Hou Family's Opportunity, Advice (Part 5)", is the clearest early answer because it turns Hou Jing's situation into a concrete plot event. A useful checkpoint is the way the scene starts with The Lingbei, Longshan, and Beehive factions in Xia City have long... and follows through with Tonight's aged wine is on me!" "Generous!" "Yang Zi is quite....