First, you need to understand the original characters well. Know their personalities, motives, and relationships. For example, the students' different assassination skills and how they interact.
One great 'assassin classroom fanfiction' story is the one where the students go on an unexpected adventure outside of the classroom setting. It really explores their characters in a new light.
Another theme could be her own growth as a character. In the series, she has her own journey, and in fanfics, this can be expanded upon. For instance, she might have to deal with personal issues outside of her teaching role, like her past relationships or her family. And how she overcomes these things can be a major part of the fanfic. It gives the author a chance to delve deeper into her character than what was shown in the original series. This can make for some really engaging stories as readers get to see a different side of her.
DeviantArt can also be a source. Sometimes, artists not only post their art but also write short fanfiction pieces related to Assassin Classroom. It might not have as extensive a collection as AO3, but the ones you find there can be really unique. They might combine art and story in an interesting way. Additionally, Reddit has some subreddits dedicated to Assassin Classroom where fans might share their favorite fanfictions or even their own works.
A great aspect is that it allows you to keep the story alive in your mind even after the anime or manga has ended. You can find fanfictions that continue the story from where it left off. Some might explore what happens to the students after they graduate. Also, reading fanfiction can introduce you to a community of fans who share similar interests. You can discuss your favorite fanfics and even get recommendations from others.
I'm sorry, I don't have specific information about 'Prof Saibaba' at hand. There could be many professors with this name. You can provide more context like his field of study, the university he is associated with, etc. to help me give a more detailed story.
I'm not entirely sure as 'chem prof fanfic' could be about a lot of things. It might be a fanfiction related to a chemistry professor. Maybe it's a story where the author creates fictional scenarios involving a chemistry teacher, like their adventures in the lab or their relationships with students in a made - up, fictionalized way.
There are probably some on Archive of Our Own as well. The great thing about AO3 is that it has a wide range of fanfics with different themes. In the case of Karasuma Irina fanfics, you might find some that are more centered around her character development, like how she becomes a better teacher or how she overcomes her own insecurities in the 'assassin classroom' world.
In a Prof Oak fanfic, the mention of blue or green Spearow could be really interesting. Maybe the color difference represents some special abilities or origins. For example, a blue Spearow might be a rare mutant form with enhanced flying speed compared to the regular ones. And a green Spearow could potentially have a closer connection to nature, like being better at finding hidden berries in the forest. However, without reading the specific fanfic, it's hard to say for sure what the significance of these colored Spearow is.