One interesting Mass Effect 3 fanfiction could be about the alternate endings. For example, a story where Shepard manages to find a completely new way to end the Reaper threat that wasn't in the original game. Another could focus on the relationships between the different species in the Mass Effect universe post - Mass Effect 3 events. Maybe a story about how the krogan and the salarians are rebuilding their trust after the genophage cure.
Some Mass Effect 3 fanfictions are about exploring new regions of the galaxy. Since the Reaper threat is over, the Alliance and other races start to send out more exploration fleets. A fanfiction could follow a young, inexperienced crew on one of these exploration missions. They could encounter new species, unknown technologies, and face various challenges in the uncharted areas of the galaxy.
There are fanfictions that center around the character development of the squad members. For instance, a story that delves deeper into Garrus' life after the war. He might be dealing with PTSD from all the battles he's been through. It could show his journey to overcome it and how his friends, especially Shepard, help him through it. Also, some fanfictions might explore Tali's role in rebuilding her homeworld, Rannoch.
There are many. Some might focus on the untold adventures of the main characters. For example, a story could be about Shepard's early days before becoming a Spectre, exploring his or her training and the relationships formed during that time in the Mass Effect universe.
Another interesting aspect could be alternate universes. Fanfiction often delves into 'what if' scenarios. Like what if Shepard made different choices at the very beginning of the game, and how that would have completely changed the course of the story and the relationships with other characters.
One interesting Mass Effect Andromeda fanfiction could be about Ryder's further adventures in uncharted regions of Andromeda. Maybe they discover a new alien species that has a unique culture and technology. Another could focus on the relationships between the different crew members on the Tempest, like a deeper exploration of the friendship or potential romance between two characters.
I'm not very familiar with specific Mass Effect futanari fanfiction stories. However, generally in Mass Effect fanfiction, there could be stories that explore new adventures for the characters, perhaps alternative versions of the main plot. But it's important to note that fanfiction varies greatly in quality and content.
One interesting 'Mass Effect OC Fanfiction' could be about an OC (Original Character) who is a biotic with a unique power that she has to keep hidden from the Council. This OC might find herself in the middle of a conspiracy that links back to the Protheans.
One interesting 'Mass Effect Synthesis Fanfiction' could be about how the characters adapt to the new post - synthesis world. For example, Shepard might have to deal with the changed relationships among different species. Another could focus on the ethical dilemmas that the synthesis brings, like whether it was truly the right choice for the galaxy's future.
The relationship between Shepard and Garrus can also be seen as a kind of love story in a way. They are comrades at first, but as they face countless challenges side by side, a deep friendship forms that has elements of love. They trust each other completely and would sacrifice for one another without hesitation.
Another type of 'Mass Effect Fanfic' could be a time - travel one. Picture Shepard being sent back in time to the days before the first contact war. With the knowledge of the future, Shepard tries to prevent certain events from happening that would lead to a lot of destruction and chaos in the future. This could completely change the course of the Mass Effect universe as we know it.
There are many. For example, some fanfictions might focus on a crossover between the two universes. Imagine a Mass Effect character like Shepard meeting a Star Wars Jedi. It could lead to really unique scenarios where different technologies and powers interact.
One interesting 'Mass Effect Star Wars' fanfiction could be about a character from Mass Effect getting transported to the Star Wars universe and having to adapt to the Force. They might struggle with the different technologies and cultures. For example, a Krogan might be confused by the lightsabers and Jedi mind tricks.