One interesting plot could be that Hermione accidentally drinks a love potion meant for someone else and starts having strange feelings towards Harry. Harry, being the noble friend he is, tries to figure out how to reverse the effects without hurting Hermione's feelings.
Maybe in the fanfic, a love potion gets mixed up in a potion class and both Harry and Hermione are affected in different ways. Harry might think his newfound feelings for Hermione are real at first, but then they start to suspect something is off when the potion's effects start to wane. They then have to deal with the awkwardness that follows.
In a more complex plot, a villain uses a love potion on Hermione to make her lead Harry into a trap. However, Hermione's strong will and her friendship with Harry start to fight against the potion's effects. She leaves little clues for Harry to figure out that something is wrong, and together they manage to turn the tables on the villain.
One common plot is that someone accidentally slips a love potion to either Harry or Hermione, which then causes all sorts of comical and sometimes complicated situations. For example, if Hermione is affected, she might start acting completely out of character around Harry, like being overly affectionate and forgetting about her usual studious nature. It can also lead to misunderstandings between them and their friends, as others try to figure out what's wrong with the suddenly love - struck character.
One popular fanfiction idea could be that Hermione accidentally consumes a love potion meant for someone else. She then starts acting out of character, perhaps showing an excessive amount of affection towards an unexpected character. This could create chaos in Hogwarts as her friends try to figure out what's wrong and reverse the effects.
There could be a fanfic where the love potion is used as a plot device to create tension between Harry and his friends. For example, if his friends suspect he's under the influence of a love potion when he starts showing interest in a particular character, and they try to figure out what's really going on while also dealing with their own feelings about the situation. This can lead to a lot of drama and character development.
In some 'love potion' Harry Potter fanfics, the plot might revolve around a love potion being used as a weapon. Maybe a dark wizard or witch uses a powerful love potion to manipulate a group of students into doing their bidding. Harry and his friends would then have to find an antidote and stop the villain's plan. This could involve a lot of adventure, like sneaking into the potions classroom at Hogwarts to find the recipe for the antidote.
Well, a plot could be that a mischievous student at Hogwarts creates a love potion and it somehow gets spilled near Ginny. Harry, who has always been a bit oblivious to his feelings for Ginny, suddenly finds himself extremely attracted to her in a way he can't explain. Ginny, on the other hand, is confused by Harry's sudden change in behavior.
One possible plot could be that Ron accidentally drinks a love potion meant for someone else. He then starts acting completely out of character, lavishing attention on the wrong person. For example, he might start writing love poems and serenading them in the Great Hall, much to the confusion and amusement of his friends.
It could show how a love potion disrupts their normal, platonic relationship. For example, if Hermione is under the influence of a love potion, she might act in ways that are out of character, like being overly clingy to Harry. This would make Harry question their relationship and his own feelings.
One possible plot could be that they have to keep their relationship a secret from Ron, who might be jealous. So they meet in hidden corners of Hogwarts, like the Room of Requirement, to spend time together.
In some 'Harry and Hermione get married fanfic', they might have to deal with a new dark threat that emerges right after their wedding. This threat could be related to a long - lost dark magic artifact that the villains want to use to take over the wizarding world. Harry and Hermione, being the intelligent and powerful couple they are, use their wits and magic to fight against this new evil. They might even get help from some unexpected allies from different houses in Hogwarts.
One interesting plot could be them facing magical challenges together from a young age. Since they are raised together, they might have a unique bond that helps them solve puzzles and overcome dark forces more easily. For example, they could encounter a mysterious magical creature in their backyard and figure out how to deal with it using their combined knowledge and skills.