A typical plot device could be the influence of an outside force. Say, a kind wizard or witch comes to the Dursleys and makes them understand the importance of Harry and his magic, and then they start to love him. Also, it could be that Harry himself shows extraordinary kindness towards the Dursleys in a difficult situation, which melts their cold hearts and changes their attitude towards him.
In 'the dursleys love harry fanfiction', often there is a plot device where the Dursleys start to see Harry's potential benefits to their family. Maybe they realize that Harry's magical abilities can be used to improve their social status or financial situation in the Muggle world. Or perhaps they begin to understand the value of Harry's magical knowledge and how it can protect them from certain threats. This new perspective makes them love Harry instead of resenting him.
One common plot device is the 'what - if' scenario. For example, what if Hermione had been the one to save Harry from the Dementors instead of his father's Patronus? This can lead to a deeper emotional connection between them. Another is the 'arranged - relationship' plot, where they are forced to pretend to be in a relationship for some magical reason, but end up falling in love for real. Also, the 'jealousy' plot device, where they get jealous of each other's relationships with other characters and realize their true feelings.
One common plot device is the redemption arc. Narcissa may be portrayed as turning away from the dark side, and Harry, seeing this change, is drawn to her. Another is the protection plot, like Narcissa protecting Harry for some reason, which then leads to a bond between them. And sometimes, there's a magical bond or curse that forces them to interact and eventually fall in love.
A plot device could be Cedric getting involved in Harry's personal quests. For instance, if Harry is trying to figure out something about his parents, Cedric may insert himself into the situation, believing he can protect Harry better that way. He might also try to monopolize Harry's time for training or studying, which could lead to some tension between them as Harry might feel smothered.
Well, a typical plot device is the danger that drives Harry to the Malfoys' in the first place. It could be that he's being chased by Death Eaters or some other dark force. Then, there's the element of family opposition. Their families have been enemies, so the relationship is forbidden in a sense, which adds to the drama. And often, there's the character growth aspect. Both Harry and the Malfoy character grow as individuals while falling in love, like Harry learning to see beyond the Malfoy family's bad reputation and the Malfoy learning about true friendship and love from Harry.
One common plot device is the introduction of a new mentor figure. This person could be an older student, a former Hogwarts graduate, or even a magical creature. They guide Harry in his studies, offer advice on how to handle difficult subjects and professors.
One common plot device is the discovery of ancient artifacts or prophecies that link Harry to Merlin. For example, a magical amulet that was once Merlin's might be found and react only to Harry. Another is the appearance of a character who knew Merlin in the past and recognizes Harry as his reincarnation.
One common plot device is mutual protection. For instance, if one of them is in danger from some dark wizards or a magical accident, the other steps in to save them. This act of heroism creates a bond of trust and friendship.
One common plot device is the slow - burn relationship. They start as friends or comrades and gradually develop feelings over time. Another is the use of a common enemy or a difficult mission that brings them closer. For example, they might have to team up against a powerful new villain and in the process, realize their feelings for each other.
One common plot device is the 'forced proximity'. For example, they might be on a mission together where they have to rely on each other. Another is the 'healing factor', where Hinata helps Sasuke deal with his inner demons. Maybe she uses her kind heart to make him see a different side of life.
A typical plot device is the discovery of rare Pokemon. In these fanfictions, the main character might stumble upon a very rare Pokemon, and this encounter could attract other characters or Pokemon, gradually forming the harem. Also, the mystery element, such as an unknown power or a hidden place related to Pokemon, can bring the harem members together as they explore and solve it. And of course, the training montages where the trainer helps the Pokemon in the harem grow stronger are quite common too.