One common theme is friendship. Despite coming from different houses and having different backgrounds, they learn to get along and support each other. Another theme could be mystery - solving. Given Hermione's inquisitive nature and Harry's knack for getting into strange situations, Blaise might be drawn into their adventures to solve mysteries around Hogwarts or in the wizarding world at large.
Another theme is the exploration of the wizarding world from their combined perspectives. Fanfictions often use their relationship as a means to show different aspects of magic, Hogwarts, or the wizarding society that might not be as easily explored through other characters. For example, they might go on adventures in less - known parts of the wizarding world.
One common theme is redemption. Draco and Blaise, especially Draco as he was a former Death Eater supporter, often have a journey of self - discovery and redemption in these fanfictions. Hermione usually plays a role in either facilitating or being a part of that change. Another theme is the exploration of relationships that cross traditional boundaries, like the relationship between a Muggle - born like Hermione and pure - bloods Draco and Blaise.
One common theme is the overcoming of differences. Hermione is from Gryffindor, known for courage, while Blaise is from Slytherin, often associated with cunning. Fanfictions usually explore how they bridge this gap. For example, in many stories, they learn to understand and respect each other's values.
One common theme is the breaking of house stereotypes. Since Blaise is from Slytherin and Hermione from Gryffindor, fanfics often explore how they overcome the prejudices associated with their houses to be together.
One common theme is personal growth. Since it's about their mature versions, both Hermione and Blaise often have to deal with their past traumas and grow from them. For example, Hermione might have to come to terms with her experiences during the war, and Blaise with his family's expectations.
One common theme is the forbidden love aspect. Since they are from different houses in Hogwarts, there's often a sense of it being against the norm. Another theme could be Blaise's admiration for Hermione's intelligence, which might be the root of his obsession.
One common theme is the clash of cultures. Hermione is from a more Muggle - friendly background and Blaise from a pure - blood family. Their different views on marriage law often reflect this divide.
One common theme is friendship. Many fanfictions explore how these three characters, who start off with a lot of animosity, especially Harry and Draco, can form a friendship. Another theme is rivalry turned into cooperation.
One common theme is redemption. Often, Draco is shown on a path of redeeming himself and his relationship with Harry and Blaise plays a part in that journey. Another theme is friendship. They start from being enemies or at least indifferent to each other and develop a deep friendship over time.
Love against all odds is also a popular theme. Their different backgrounds and the expectations within the wizarding world make their relationship a struggle, but that's what makes it so appealing in the fanfictions.