I don't have enough information to say who the main characters are. It could be anyone from a troubled anti - hero to an ordinary person who has made some bad choices and now has to face the consequences.
There's no way to know for sure without reading the graphic novel. However, the main characters could be those who are living in a world where karma is a governing force. It could be a group of people, like a family where one member's bad karma starts to affect the whole family. Or it could be a lone character who is on a journey to understand and overcome their bad karma. They might be from different backgrounds, such as a businessperson who has been unethical in their dealings or an artist who has stolen ideas and now has to face the music. The possibilities are really open - ended.
Since we don't know the exact 'karma graphic novel' in question, the main characters could be anyone really. It could be a group of friends who experience different karmic situations together. Maybe one of them is a skeptic about karma and the others try to convince them. Or it could be a single character who has a life - changing experience related to karma, like a person who has always been selfish but then starts to see the error of their ways through a series of events that seem to be karmically - driven.
I'm not sure specifically as I haven't read it. But generally, a graphic novel with 'bad karma' in the title might be about the consequences of negative actions or a character's journey through a world where bad karma plays a significant role.
The main characters in 'bad friends graphic novel' could be diverse. There may be a character who is a bit of an outcast, someone who has a troubled past. And there could be others who are drawn to this character for various reasons. They form this group of 'bad friends' and through their interactions, the story unfolds. Maybe there's a leader - type character who is constantly getting them into trouble and a more timid character who is always on the verge of leaving the group but never quite does.
I'm not sure exactly, but probably some characters who are initially seen as villains.
Without more information, it's impossible to say who the main characters are.
I don't have enough information to say for sure. But surely there would be the 'bad doctor' as a main character. There might also be patients who are affected by the doctor's actions, or other medical staff who either oppose or are complicit in the doctor's bad behavior.
I don't know for sure as I haven't read it. But likely there's the bad doctor himself. There might also be patients who are affected by his actions, and perhaps other medical staff who either oppose or are complicit in his deeds.
Since I'm not familiar with the 'bad machinery graphic novel', the main characters could be a diverse group. There might be a young, curious protagonist who discovers the issues with the machinery first. There could also be an older, more experienced character like a veteran mechanic who has seen similar problems before and tries to guide the others. And perhaps there are some antagonists as well, like the people or forces that are responsible for the machinery being bad in the first place, whether it's due to negligence, greed, or some other reason.
I don't have enough details to know the main characters. But they could be survivors if the story is about a disaster - like a brave sailor, a resourceful young person, or an experienced adventurer.
Since I haven't read it, I can't say for sure. But it's likely that the bad sister herself is a main character. There might also be other family members like her parents, siblings (if she has more than one), or maybe a best friend who is either influenced by her or trying to change her.