Their relationship could develop through shared hobbies. For instance, if Penny starts to show more interest in Leonard's scientific work, it can bring them closer. They can have deep conversations about his research, and Leonard can teach her new things.
Maybe in the fanfiction, Penny and Leonard decide to have a big party after getting married to celebrate with all their friends and family. There could be a lot of humorous moments, like Sheldon trying to take over the party planning with his own unique rules.
A popular story could be about how they first met and the initial attraction. Leonard was smitten with Penny right from the start, and Penny gradually saw the good in Leonard. Their first date, which was filled with nervousness and some awkward moments, was a key part of their relationship's origin. Also, their story of living together brought new challenges and joys. They had to learn to share space, deal with each other's habits, and that was an important aspect of their relationship development.
Well, it's possible that Mang gets back together. But we need to know more details about the situation, like the reason for the initial split and the efforts made by both parties since then.
The story of a broken mirror being reunited usually referred to the story of two people who broke up for some reason but met again under some chance or coincidence and got back together. This kind of novel usually involved the emotional entanglement between two people and the various challenges and difficulties they faced after they got back together. Some novels would also describe the conflicts and misunderstandings between the two and how they would resolve these estrangement after they got back together.
We can focus on their friendship. Their friendship was the foundation of their relationship. We can write about the times they just hung out as friends, like when they watched movies together or had game nights with their friends. This shows a positive side of their relationship without any inappropriate elements.
A typical theme would be the support system around them. Their friends would play a big role in this fanfiction. For example, Sheldon might struggle with the idea of there being a baby in his close - knit group but still end up being surprisingly helpful. And the theme of family could be explored, not just the family they are creating but also their extended families. Maybe Penny's family has some old - fashioned ideas about pregnancy and child - rearing that conflict with what she and Leonard want, leading to some interesting plot twists.