Nana Komatsu and Masaki Suga had worked together in the movie Drowning Knife, but there was no mention of them acting in a TV series together. There was currently no relevant information regarding their cooperation in the TV series.
Since I don't know the real nana komatsu and masaki suda, let's imagine their love story. They could have been friends first. Then one day, nana komatsu got into some trouble and masaki suda was there to help her out. That event made nana komatsu see masaki suda in a new light. They started to spend more time together, and feelings of love began to blossom. Their relationship might have faced some challenges, like family disapproval or long - distance issues, but they overcame them through their strong love for each other.
As I don't have the real story, I can only speculate. Maybe their first kiss was a key moment. It could have been a very emotional and passionate moment that deepened their connection. Another key moment might be when they said 'I love you' to each other for the first time. It was a declaration of their feelings and made their relationship more serious.
One popular idea could be exploring their friendship in different settings, like them traveling together. Another could be a story where they support each other through difficult times in their careers. And they could also have a story where they start a new business together.
To start a nana x hachi fanfic, begin by brainstorming different scenarios. Think about the kind of relationship you want to portray between them, whether it's more of a sisterly bond or a deeper emotional connection. After that, create an outline that includes the beginning, middle, and end of your story. For example, start with an interesting encounter, then build up the tension or conflict in the middle, and finally resolve it at the end.