It could be a dark wizard who is jealous of the relationship between Harry and Madame Maxime. This wizard might see their alliance as a threat to his own plans for power and try to break them apart.
An ancient evil spirit that has been awakened due to some magical experiments could be the antagonist. This spirit could target Harry because of his connection to Voldemort and Madame Maxime because of her powerful magic. It would try to possess them or use their magic for its own malevolent purposes. The fanfiction could then be about Harry and Madame Maxime fighting against this spirit and finding a way to banish it.
Harry Potter and Madame Maxime are the central figures in this fanfiction. However, depending on the specific plot, other characters like Dumbledore or the students at Hogwarts could play supporting roles. But the interactions between Harry and Madame Maxime, which could range from her guiding Harry in his magical studies to a more complex emotional or romantic relationship as is typical in lemon fanfiction, are what the story is mainly about.
A plot twist could be that Madame Maxime, being half - giant, imparts some of her physical and mental toughness on Harry. This makes him a more formidable opponent in duels and other challenges. In the story, this might lead to him being targeted earlier by Voldemort's forces because they see him as a greater threat. Also, the Beauxbatons Academy environment, which he would be more familiar with due to being raised by Madame Maxime, could have different magical traditions. These traditions could either help or hinder Harry when it comes to facing the Dark Lord. For instance, they might have different ways of casting defensive spells that Harry has to adapt to the British magical world.
One common theme could be the exploration of Madame Maxime's character in a more romantic or sensual context, which the 'lemon' aspect might suggest. Another could be her relationships with other characters from the Harry Potter universe, perhaps with characters from Beauxbatons or even with some Hogwarts staff.
Finding 'Harry Potter Madame Maxime Lemon' fanfiction can be a bit tricky. The 'lemon' aspect usually implies some romantic or spicy content. However, not all fanfiction platforms allow such content. You could start by looking at the more well - known HP fanfiction communities. Maybe ask around in forums dedicated to Harry Potter fanfiction. There might be some readers who can point you in the right direction.
A plot could revolve around Madame Maxime and Harry going on a secret mission together. Maybe they have to retrieve a powerful magical artifact that has ties to both Hogwarts and Beauxbatons. This would involve them facing various magical creatures and dark wizards along the way. They would have to learn to trust each other and combine their different magical skills to succeed.
In some fanfictions, there could be a plot where Madame Maxime and Harry Potter are involved in a magical competition that takes an unexpected turn. Due to some unforeseen circumstances, they have to work closely together, and during this time, their relationship deepens. This might include some moments of jealousy from other characters, and as the story progresses, their relationship might take on a more romantic or at least a very close friendship aspect with elements that are characteristic of lemon fanfiction, like some tender or passionate moments between them.
Since Madame Maxime would expose Harry to different magical cultures, his magic could develop in a more diverse way. He could have a better understanding of magic related to magical creatures, like using magic to communicate with veelas or control giants. This would be different from the more traditional Hogwarts curriculum that focuses mainly on spells for general use. His magic could also be more attuned to the environment of the French wizarding world, which might have different ley lines or sources of magical energy.
Perhaps a long - lost relative of the Potter family who feels they were unjustly excluded from inheriting the manor. This relative could be jealous of Harry's status and the wealth associated with the manor. They might use dark magic to try and claim what they think is rightfully theirs, leading to a battle of magic and loyalty within the Potter family and among Harry's friends.
A new dark wizard or witch could be created specifically for this fanfiction. This character could be interested in using the Huntsman's skills for their own evil purposes. If the Huntsman refuses, they become enemies. This antagonist could have powers related to dark forest magic, something that the Huntsman is familiar with but in a more malevolent form.
Voldemort could still be the main antagonist. Even if Demetri has some sort of connection or change in the fanfiction, Voldemort's overarching evil plans would still be a major threat to both Harry and Demetri, especially if Demetri tries to deviate from the Death Eaters' path.