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.
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.
One concept could be that Villain Deku manages to manipulate Bakugou into joining his side. Maybe he plays on Bakugou's insecurities or his desire for power. Another could be a world where they are both villains from the start and they form a power - hungry duo, causing chaos everywhere. A third concept might be that Villain Deku kidnaps Bakugou as part of a grand scheme to get back at the hero society that they both feel has wronged them in some way.
Some characters might try to understand Deku's motives. Kirishima, who was close to Bakugou, would be angry at first but might also try to find out if there were any extenuating circumstances. However, many would be afraid of Deku, seeing him as a threat now that he has killed one of their own.
Well, AO3 is definitely a great place to start. It has a tagging system that makes it easy to find the specific type of fanfic you're looking for. When you search for 'villain deku x bakugou', you can also filter the results by things like rating, word count, and completion status. Fanfiction.net also has a decent selection. However, you need to be a bit more careful there as the quality control isn't as strict as on AO3. You could also look into Tumblr. There are a lot of My Hero Academia fans on Tumblr who might post about or recommend good villain deku x bakugou fanfics. Some of them might even have their own fanfic blogs where they share their work.
A possible plot is a power struggle between them. Since Deku has turned villain, he might see Bakugou as a threat to his plans. Bakugou, on the other hand, wants to bring Deku back to the light. This creates a constant back - and - forth of battles, both physical and psychological, as they try to outwit each other.
Deku might be initially shocked. He's used to Bakugou's aggression, but an actual injury is different. He could be in pain and disbelief at first. Then, he might try to downplay it, especially if he doesn't want to cause trouble for Bakugou, because Deku is generally a very forgiving character.
No, it's not appropriate. Deku is a character with his own depth, goals, and story within the MHA universe. Fanfic should aim to explore his hero journey, his relationships in terms of mutual respect and support, not create content that focuses on inappropriate or disrespectful ideas like this.
It could start with Deku taunting Bakugou. As a villain, Deku would have a new - found confidence and would use it to get under Bakugou's skin. He might leave cryptic messages for Bakugou, hinting at their past and how Bakugou used to bully him. This would make Bakugou angry but also curious about what Deku has become.
Well, I'm not sure about a specific 'deku x bakugou dies fanfiction' that is the best. However, many fanfiction writers might explore this concept in different ways. Some might focus on the emotional aftermath for the other characters, while others could create alternate universes where this event leads to a whole new set of adventures or challenges for the remaining characters in the My Hero Academia universe.