The setting of their world. Their world is full of magic and mystery. A fanfic can explore different parts of this world that we haven't seen much in the original works. It could take the readers on a journey through the dark forests where Wriggle lives among the bugs, or to the places where Mystia sings her enchanting songs. This exploration of the setting can make the fanfic really engaging.
Well, it's hard to say for sure. Sometimes a Touhou comic might stick closely to certain expectations, while in other cases it could take some creative liberties and deviate.
I'm not entirely sure as I haven't read it specifically. But generally, an 'isekai' often involves a character being transported to another world. An 'izakaya' is a Japanese pub - so perhaps it's about a character who gets transported to a world where an izakaya called Nobu plays a significant role.
I'm not sure if it's a popular genre on its own. Isekai is a popular genre in general, but the combination with an izakaya and specifically 'Nobu' might be quite niche. It really depends on how well the concept has been executed and marketed.
I don't have specific knowledge about the plot of 'izakaya nobu light novel'. However, generally, if it's related to an izakaya (a type of Japanese pub), the plot might revolve around the characters who work or frequent the izakaya. It could involve their daily lives, relationships, and the stories that unfold within the izakaya setting. Maybe there are some unique food descriptions and cultural elements related to izakayas as well.
Well, it could be about their adventures in the magical world they inhabit. Maybe they team up to face a common threat, like an evil spirit that is disturbing the peace of their land. They could use their unique abilities - Wriggle's power over bugs and Mystia's singing skills - to overcome challenges.
You can start by looking on some popular fanfiction websites like Archive of Our Own (AO3). It has a large collection of Touhou - related fanfictions, and there's a good chance you'll find some Mystia x Wriggle stories there. Just use the search function and type in the relevant tags.
One great Mystia x Wriggle fanfiction could be a story where they team up for a music event in Gensokyo. Mystia, with her love for singing, and Wriggle, with her unique bug - related abilities, might create an interesting dynamic. They could face challenges like dealing with a noisy audience or a rival music group, and in the process, their friendship could turn into something more romantic.
In my opinion, the story of Flandre Scarlet is also a great one in the Touhou series. Flandre is a powerful vampire who has been locked away for a long time. Her story is about her isolation, her struggle with her own power, and her attempts to interact with the outside world. It shows her complex personality, from her child - like innocence to her terrifying strength when provoked. This contrast makes her story very engaging.
Well, start by familiarizing yourself with the Touhou characters and their backstories. Then, plan out a simple storyline that fits the Touhou universe.