Well, perhaps the assassin is on a mission to take out someone who has a role in the radioactive chaos in New York. Maybe this person is hoarding resources or trying to take advantage of the situation, and the assassin is hired by those who want justice.
The assassin, of course, would be a main character. They could be a former special forces agent or a criminal who has turned their skills towards this new purpose in the post - radioactive New York. Another main character could be the target, who might be a corrupt politician or a powerful businessperson trying to profit from the chaos.
I'm not sure specifically as I haven't read it. But generally, a graphic novel like this might be about a journey into a new and different world. It could involve new characters, new cultures, and new adventures.
One real story could be about the excitement of newcomers arriving in New York. They might be drawn by the city's countless opportunities, like finding a great job in the business district. The bright lights and big buildings symbolize hope for a new life.
Well, 'harry potter radioactive fanfiction' could potentially be a story that takes the normal elements of the Harry Potter series and adds a radioactive twist. For example, it could be about a potion gone wrong that emits radiation, or a new type of magic that is related to radioactivity. It might also explore how the characters in the Harry Potter world would react to such a strange and dangerous new concept. It could be a really interesting take on the familiar wizarding world, but without actually reading it, it's hard to say for sure what it's all about.