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.
The theme of self - discovery is also prevalent. Both characters grow and learn more about themselves through their interactions. They discover new aspects of their powers, emotions, and identities as they navigate their relationship in these fanfics.
Another theme is cooperation. Given their different quirks, fanfics often explore how they can work together effectively. Like in a battle scenario, Momo can create useful items and Todoroki can provide offensive and defensive power with his ice and fire abilities.
One common theme is redemption. Since Endeavor has made many mistakes in the past regarding his family, especially with Todoroki, many fanfics focus on him trying to redeem himself. Another theme is forgiveness. Todoroki has to decide whether to forgive his father or not. And also, family bonds. They are father and son, so exploring how they can strengthen or repair their family connection is often seen in these fanfics.
One common theme is the power of friendship. Since they are both students in the hero academy, they often start as friends and then feelings might develop. Another theme is the overcoming of differences. Izuku was born without a quirk initially and Todoroki has a complex family background and powerful quirk. They learn to understand and support each other.
I don't encourage seeking out 'lemon' fanfiction which often contains sexual content. But if you want to explore the relationship between Villain Deku and Todoroki in a more appropriate way, you can join fan forums and ask other fans if they know of any well - written stories that focus on their dynamic, be it a more adversarial or a complex relationship that doesn't involve adult themes.
Power imbalance is often a theme. Deku might gain new, more dangerous powers as a villain, and Todoroki has to figure out how to deal with that. There could also be a theme of trust. Since Deku is a villain, Todoroki has to decide whether to trust him or not. And if he does trust him, it could lead to all sorts of complications in the story.
One great 'dabi x todoroki fanfic' is 'Flames of Redemption'. It explores their complex relationship in a post - war scenario. The author does a wonderful job of delving into their characters, showing how Dabi's troubled past and Todoroki's growth interact.
There's also 'Momo and Todoroki's Team - up'. In this fanfic, they are paired for a crucial mission. It shows their different strengths and how they complement each other during the mission. It's really exciting to read as they face various challenges together.
One popular Todoroki x Endeavor fanfic is 'A Father's Redemption'. It delves into the complex relationship between them, exploring how Endeavor tries to make up for his past mistakes. Another is 'The Unspoken Bond' which focuses on their shared experiences and how they gradually come to understand each other better. There's also 'Healing the Rift' which shows their journey towards a more positive relationship.