Well, Iida would probably have a very proper reaction. He might give Bakugou a stern talk about treating Deku right and being respectful on the date. Mina would be super excited and would start gossiping about it right away. She'd be all over Deku, asking him what he was going to wear and things like that. And Kaminari would probably make some silly jokes about it, like saying Bakugou was finally 'going soft' for Deku.
One possible scenario is that Bakugou finally realizes his true feelings for Deku after a long time of denying them. He might plan a really elaborate date, like taking Deku to a special place that has significance for both of them, perhaps a place where they trained together when they were younger. It could be a really emotional moment when he asks Deku out, with Bakugou being uncharacteristically nervous.
Bakugou could use his words. He might tell Deku that he believes in him. For example, he could say 'Deku, you may be a nerd but you're a strong nerd.' It's a backhanded compliment but it shows he has faith in Deku.
Deku might be completely shocked at first. Since Bakugou has always been so aggressive towards him, he would never expect such a confession. He might just stand there, mouth agape, not knowing what to say.
Bakugou may prove his love by being protective. He might put himself in danger to save Deku. In many stories, this kind of self - sacrifice is a strong indication of love. Also, he could start to understand Deku's dreams and support him in achieving them, which is a deeper form of love than just friendship.
Growth is also a prevalent theme. Both characters are on a journey of self - discovery and improvement, and fanfics usually show how they grow both as individuals and in relation to each other. For example, Bakugou learning to control his temper and Deku becoming more confident.
One common theme is rivalry. Their intense competition to be the best hero is often explored, like in many fanfics where they constantly try to outdo each other in training or in real battles. It shows their determination and drive.
To develop their relationship realistically, start with their existing dynamic. Bakugou is often aggressive towards Deku, so a slow change is needed. Maybe have them be forced to team up. As they face challenges together, Bakugou could start to respect Deku's abilities bit by bit. For example, if they are in a battle against a powerful villain and Deku comes up with a clever strategy, Bakugou might grudgingly admit Deku's smarts.
At first, it could be extremely strained. Deku might be terrified of Bakugou and avoid him at all costs. But as the story progresses, if Bakugou realizes his mistake, he could start trying to make it up to Deku. Deku, on the other hand, might be hesitant to accept Bakugou's apologies at first, but over time, they could start to rebuild a more positive relationship based on mutual respect.
The description of the dance itself is important. It should include details like the type of dance, the rhythm, and how they move in sync or not. In a good fanfic, this can create a vivid image in the reader's mind, like if it's a tango, the passion and intensity of their movements.