I don't know as I haven't read it. It could be a baker who made the toxic donut, or a customer who discovers its toxicity.
Since I'm not familiar with this exact short story, it's hard to say precisely. However, I can guess that the 'toxic donut' could be a central symbol in the story. It might represent something more than just a physical object. Maybe it stands for a corrupting influence in a community or a relationship. The story could explore how the presence of this toxic donut affects the people around it, whether they are aware of its toxicity or not. There could be different reactions among the characters, some might be tempted by it despite the danger, while others might try to get rid of it.
The main character in 'if you give a dog a donut online story' is clearly the dog. However, there could be other implied characters like the person who gives the dog the donut. But the dog is the one whose actions and reactions drive the story forward. It's the dog that decides what to do with the donut, whether it wants more things to go with it or wants to do something fun after getting it.
I don't have enough information to tell who the main characters are in this novel. It could be a couple where one is the toxic lover, like a man named Jack and a woman named Lily.
Since we don't know the details of 'the donut king story', the main character could be an entrepreneur with a passion for donuts. It might be someone who had a family recipe for donuts and decided to turn it into a business. They could be a creative person who was always thinking of new ways to make donuts more appealing, like a young baker who started from his or her home kitchen and grew into a well - known figure in the donut world.
Since we don't have the full 'donut man story', it's difficult to say exactly who the main character is. But it's likely to be the 'donut man' himself, whoever he may be in the context of the story.
Since I don't know the exact 'Donut King Story', it could be an entrepreneur who founded a famous donut chain.
Maybe the main characters are the industries that produce plastic and the environment. The industries love to produce plastic for profit, but the environment suffers from the toxicity of plastic, creating a 'toxic love story' between the two.
I'm not sure as I haven't read it. It could be a character with the 'toxic heart' as one of the main characters. Maybe there is also a healer or a guide type of character who tries to deal with the 'toxic heart' in the context of the mystic city.
Since I don't know the story, it could be Ariana herself. If the story is named after her and related to a donut shop, she might be the central figure.
Since the title doesn't give away much about the characters directly, we can only guess. It could be a young couple, like a girl and a boy. The girl could be the one with the 'wish' and the fear of having her heart broken. Or it could be about an older character who has been through a lot in love and is now hoping that this new relationship (implied by the title) doesn't end in heartbreak. There might also be a character who is a bit of a troublemaker in the story, causing some of the heartbreak - related drama.