One idea could be to explore the emotional turmoil Kagome experiences. She might be conflicted between her feelings for Inuyasha and this unexpected situation with Touga. The story could focus on how she copes with the pregnancy in a world full of demons and magic, and how the other characters react to this news.
Well, it depends on what you consider 'good'. There are definitely fanfictions out there about Kagome and Touga. Some might focus on a romantic aspect, while others could be more about a platonic bond. Try searching on popular fanfic platforms and read the reviews to find ones that suit your taste.
Often, love and loyalty are common themes. The story might revolve around how they fall in love despite their differences. Also, the theme of sacrifice can be present. For example, one of them might have to sacrifice something from their own world or way of life to be with the other. There can also be themes related to family acceptance, as their relationship may face challenges from their respective families or groups.
I haven't read that specific fanfiction, so I can't summarize it directly. But generally, in such a story, Touga might use his strength, knowledge or some special powers to rescue Kagome from a life - threatening situation. Maybe she's in danger from a powerful demon or some other perilous circumstances.
In such a fanfiction, there could be emotional turmoil for Kagome, potential marital problems for Touga, and maybe social stigma. It's a recipe for a lot of chaos and heartache.
One plot twist could be that Touga is actually in league with the ones who put Kagome in danger at first, but then has a change of heart. Another could be that the method to save Kagome is something completely unexpected, like it requires a sacrifice from Touga that he wasn't aware of when he started the rescue.
First, avoid making it overly sexualized. Focus on the emotional and plot - driven aspects. For example, you can write about the shock and confusion that Kagome feels when she discovers she's pregnant. This can be a starting point for exploring her character development further.