A 'villain deku x villain todoroki fanfiction' might focus on their backstories that led them to become villains. It could be that they were both wronged by the hero system in some way. Deku might have been rejected too many times or faced unfair treatment, and Todoroki could have some family - related issues that pushed him to the dark side. The story could then show how they form an alliance and start their villainous journey together.
One possible plot could be that Villain Deku is on a mission to undermine the hero society and crosses paths with Hero Deku. They engage in a fierce battle where Villain Deku taunts Hero Deku about his ideals. In the end, Hero Deku manages to get through to a small part of Villain Deku's conscience, leaving him with some doubts about his villainous path.
Their relationship could start with mutual self - interest. They both recognize the power and chaos the other can bring. For example, Toga's ability to transform could help Villain Deku infiltrate places, and he can offer her protection in return.
The relationship could start with hatred. Bakugou may initially be enraged that Deku has become a villain. But as time passes, he starts to see the reasons behind Deku's transformation, which could lead to a more complex relationship.
In 'villain deku fanfiction', a frequent theme is the subversion of expectations. Since Deku was initially seen as a pure - hearted hero, seeing him as a villain completely turns that on its head. Another theme is the power struggle. He has to fight against the heroes he once called allies. The theme of identity crisis is also there. He is no longer the Deku everyone knew, and he has to redefine himself as a villain. There's also the theme of the dark side of heroism, showing that the very qualities that could have made him a great hero can be twisted into making him a terrifying villain.
The 'Villain Todoroki x Deku' fanfiction might also focus on power dynamics. Since both characters have strong quirks, how they use or misuse their powers in relation to each other can be fascinating. For example, Todoroki's ice and fire powers could be used in more menacing ways as a villain, and Deku would have to find new strategies to counter him while still trying to save him from his villainous ways.
Well, in such a fanfiction, it often explores a different side of Deku being a villain and his relationship with Todoroki. It could be about how their dynamic changes from the original story. Maybe Deku as a villain has different motives and goals that somehow involve Todoroki, like trying to use Todoroki's power for his own evil plans or trying to turn Todoroki to his side.
Perhaps they get involved in a power struggle within the villain world. They want to prove themselves as the most feared villains. This could lead to battles with other villains and alliances with some unexpected characters. It could also involve them trying to steal some powerful artifacts or secrets from the hero side to gain an edge in their villainous activities.