Since I don't know the specific 'bad end friends story', it's hard to say who the characters are. But generally, there would likely be at least two friends. They could be friends from school, like classmates who have different personalities. Maybe one is more outgoing and the other is shy, and their differences cause problems in the end.
The 'bad end friends story' might be centered around a series of events that test the friendship. For example, if the friends are involved in a competition, jealousy could rear its ugly head. One friend might feel that the other is getting more attention or opportunities, and this envy could lead to backstabbing or other harmful behaviors. Or it could be a situation where a friend makes a big mistake and the others can't forgive them, resulting in the end of the friendship.
One idea could be to explore a scenario where friends turn on each other due to a misunderstanding over a valuable heirloom. Maybe one friend was entrusted with it for safekeeping but lost it, and the others think it was stolen on purpose.
One common theme could be betrayal. For example, a friend might betray another for personal gain, like stealing a job opportunity that was promised to the other friend. Another theme could be miscommunication. Friends might misunderstand each other's intentions and end up in a bad situation. Also, jealousy can play a part. If one friend is jealous of the other's success or relationships, it can lead to a bad end in their friendship.
Since I don't know the details of this story, it's hard to summarize. However, generally speaking, to summarize a story, you need to look at the main character Marco's experiences, the conflicts he faces, and how the story ends. Maybe there are some important events or relationships in it that are crucial for summarizing.
Another theme might be betrayal. Maybe someone in Marco's friend group betrays him, which leads to the bad end. It could also be about the consequences of bad choices. If Marco or his friends make wrong decisions, it could result in the negative outcome for their friendship as shown in the story.
Well, it depends on your perspective. But generally, Negan is considered bad in the comic because of his cruel and violent actions towards the main characters.