In writing Genos x Cheating OC fanfiction, a major challenge is creating a believable and engaging plot. The idea of cheating is not easy to work with as it can quickly turn the story into a melodrama. You need to find a balance between showing the relationship between Genos and the OC, and dealing with the cheating aspect. Moreover, you have to consider the reactions of the other characters in the Genos - related universe. Will they condemn the cheating? How will it affect the overall story arc? And finally, making the story unique and not just a rehash of typical cheating stories is a real test for the writer.
One challenge is dealing with the negative perception of cheating. Readers may be put off by the idea and it can be hard to make them sympathetic to the characters involved. Another challenge is staying true to the character of Genos. His personality and values need to be considered when writing him in such a complex and morally ambiguous situation.
Well, for starters, you have to handle the emotional aspects carefully. Since cheating is involved, the emotions of the characters, especially the wronged ones, can be intense. And when it comes to Genos, his robotic nature adds another layer of complexity. How does he, as a cyborg, react to the concept of cheating? Does he understand the human emotions behind it? Also, making the OC believable in this situation and having a good reason for the cheating (if there is one) is not easy.