I'm not sure as I haven't read it, so I can't tell who the main characters are.
Not having read the novel, it's difficult to determine the main characters precisely. However, we can assume that there might be a protagonist who is at the center of the kiss - curse situation. This character could be a young person, perhaps a female or male lead. There may also be a supporting character, like a wise old figure who has some knowledge about the curse and tries to guide the protagonist. And there could be a character who is somehow involved in the creation or continuation of the curse, acting as an obstacle to the protagonist's attempt to break free from the curse.
There's a good chance that the king is a main character. Alongside him, there could be a love interest for the king, who is deeply affected by the curse. There may also be a seer or a prophet who has some knowledge about the curse and its solution. Additionally, there could be traitors within the king's court, which adds more drama to the story as they either try to take advantage of the king's weakened state or prevent the curse from being lifted.
I don't know who the main characters are in 'the curse of desire novel' as I haven't read it.
Since we don't know the details of 'the kiss novel', the main characters could be very diverse. They could be two people from different cultural backgrounds whose kiss bridges the gap between their cultures. Or perhaps it's about two friends who realize their deeper feelings through a kiss, and these friends would be the main characters. There could also be a story where an older and a younger character share a kiss, and they are the central figures around which the story revolves.
I don't know for sure. But I would guess the dragon king himself is a main character. There might also be a brave knight or a wise mage.
The main characters are Captain Jack Sparrow, that flamboyant and unpredictable pirate. Elizabeth Swann, a young woman from a more civilized world who finds herself in the midst of pirate adventures. Then there's Will Turner, a skilled blacksmith with a connection to the pirates. There might also be Barbossa, the captain of the Black Pearl when it's under the curse. He's a formidable and cunning adversary.
Since I'm not familiar with the 'curse of yhe gods novel', the main characters could be a group of adventurers. They might be on a quest to find a way to end the curse. There could also be a powerful wizard or sorcerer who has some knowledge about the curse and is guiding the others. Or perhaps there is a chosen one among them with a special ability to deal with the gods' curse.
Maybe there are powerful gods and demons as main characters. The gods could be trying to maintain their order and the demons might be causing chaos with the curse. There might also be a mediator - type character, perhaps a wizard or a special being, who is trying to find a solution to the curse - related problems.
I'm not sure exactly as I haven't read it. But usually in a light novel, there would be a protagonist who is likely at the center of the story dealing with the heavenly curse. There may also be a mentor - like character to guide the protagonist.
It's possible that there are multiple main characters. One could be a young woman who discovers she is under Cupid's Curse and is desperate to find a way out. Another could be a man who she meets along the way and who has some connection to the curse, either he has been sent to help her or he is also a victim. And then there could be an older character, perhaps a wise woman in the village, who has knowledge of ancient love curses and tries to guide the young woman in her quest to break the curse.
Since I haven't read this fanfic, I can't say for sure who the main characters are. They could be original characters created by the fanfic writer, or they could be characters from the source material that the fanfic is based on.