One common theme is friendship turning into something more. Since they are friends in the original series, fanfiction often explores the idea of their relationship evolving romantically.
One common theme could be friendship evolving into something more. Maybe they start as friends and gradually develop romantic feelings. Another theme might be adventure. They could go on an adventure together and their relationship deepens during that journey.
Some of the best nozomi x maki fanfiction can be found on Archive of Our Own (AO3) as well. It has a large collection of fan - created works. You might want to look for stories with high ratings and a lot of kudos, which usually indicate good quality.
There's 'Yuji and Nobara: Unseen Connections'. This fanfic delves deep into their friendship that could potentially turn into something more. It has some really interesting scenarios where they rely on each other's strengths and learn from their weaknesses.
I'm sorry, I don't have specific fanfiction to recommend directly. But you can try searching on popular fanfiction websites like Archive of Our Own or FanFiction.net. Just type in 'yasuhiro x honoka maki' in their search bars, and you should be able to find some stories written by fans.
One common theme could be friendship. Given the nature of the characters in 'inu x boku ss', the fanfics might explore the deepening of friendships between the characters. For example, Nobara and other characters might have storylines that revolve around how they become closer friends and support each other.