A fanfiction could explore 10k's backstory more in - depth. Maybe he had a family before the apocalypse that he is constantly reminded of during his travels. This could add a whole new emotional layer to his character.
Another idea for a fanfiction involving 10K in Z Nation is a time - travel scenario. What if 10K somehow got sent back in time to before the zombie outbreak? He could use his knowledge of the future to try and prevent the apocalypse, or at least change some things to make survival easier for everyone.
Survival is a very common theme. Since it's set in the Z Nation world, characters like 10k are constantly fighting for their lives against zombies. Another theme is friendship, like the bond between 10k and his comrades. They rely on each other to get through tough situations.
In a fanfiction, 10K might get separated from his group. He then has to survive on his own in a very hostile environment filled with not only zombies but also other dangerous humans. During this time, he could learn new survival skills and also face some of his inner demons. He might even meet some new allies along the way who help him reunite with his group.
One great 10k z nation fanfiction could be about 10k's journey before he joined the main group. It might explore his early days surviving alone and how he developed his skills. Another could focus on a romantic relationship for 10k within the post - apocalyptic world of Z Nation. Maybe he meets a girl who also has a special ability and they team up to fight the zombies together.
A more complex fanfiction could involve a crossover of the two universes' viruses. The virus in Z Nation and the vampire virus in Twilight somehow interact. Bella, being in the middle of it, has to figure out how to stop a new, more dangerous threat that emerges from the combination of these two 'viruses'.
Survival is a very common theme. Given the post - apocalyptic setting of 'Z Nation', fanfics often revolve around 10k and other characters trying to stay alive among the zombies. They need to find food, shelter and avoid getting bitten.
Addy would also be a good choice. She is strong and resourceful. In a fanfiction, she and 10k could go on a mission to find a cure together. Their different personalities would create interesting dynamics as they face various obstacles along the way.
There could be many interesting scenarios in such a fanfiction. Maybe 10k, with his survival skills from Z Nation, ends up in the Twilight universe and meets Bella Swan. He could help her in a different way from the Cullens, perhaps using his combat skills against some new threats in Forks.
I'm not sure if there is specific fanfiction about 10k being abused in Z Nation. Fanfiction can cover a wide range of themes, but this one might be a rather dark and not so common theme. It could exist in some corners of the fanfiction world, but it would also depend on the creativity and interests of the individual fanfic writers.
One idea could be a crossover where Naruto characters end up in the Z Nation world. For example, Naruto with his shadow clone jutsu could be really useful against the zombies. He could send out clones to distract the zombies while the group tries to find a safe place.