Well, there's the 'Redemption Harem' trope. Some characters in the Harry Potter universe who might have been on the wrong side initially, like Draco in some interpretations, could be part of Harry's harem as a form of redemption for their past actions. Then there's the 'Time - Travel Harem' where Harry, through some time - traveling adventure, gathers a harem from different time periods in the wizarding world. And don't forget the 'Muggle - Born Harem' trope, where Muggle - born witches who are often looked down upon in the original series, find strength and love in Harry's harem.
One popular trope is the 'Chosen One's Harem'. Since Harry is the Chosen One in the Potterverse, having a harem around him can play on the idea of different characters being drawn to his power and destiny. Another is the 'School Harem' as Hogwarts is a central setting. Girls (or guys in some fics) from different houses might form a harem around Harry due to his heroics in school. Also, the 'Magical Bond Harem' where magical bonds, like a soul - mate type of bond, connect Harry to multiple characters in the harem.
A common trope is the 'Power - Balance Harem'. Harry has a certain amount of power as a wizard, and in some fanfictions, the harem members are chosen to balance out his power, either by complementing it or challenging it. For example, Hermione with her intelligence can help Harry make more strategic decisions. There's also the 'Secret Identity Harem' trope. Harry might have a secret identity, perhaps as a powerful wizard in a different form, and a harem forms around this secret side of him. Another one is the 'Found Family Harem' where the harem members become like a family to Harry, giving him the love and support he lacked growing up.
One popular trope is the 'fish out of water' situation where the main character, often a self - insert or an OC, finds themselves in the middle of a harem of Harry Potter characters. Another is the 'enemies to lovers' within the harem, where some of the characters initially dislike the main character but then fall for them. Also, the 'power - up' trope is common, where the main character gains new magical abilities or knowledge through their interactions with the harem members.
One common trope is the 'fish out of water' situation where the main character, often a new addition to the wizarding world, attracts the attention of multiple male characters. For example, a Muggle - born witch suddenly finding herself in the middle of a group of Hogwarts heartthrobs. Another trope is the 'forbidden love' aspect, like falling in love with a Slytherin when you're from Gryffindor and having to deal with the house rivalries within the reverse harem. There's also the 'powerful heroine' trope, where the female lead has some unique power or ability that makes her stand out and draws the guys to her.
One common trope is the 'fish out of water' situation for Harry. In a harem fanfic, he might be suddenly surrounded by a group of characters who are romantically interested in him, and he has to navigate these new relationships while still dealing with his wizarding world duties, like fighting Voldemort. Another trope could be the 'power couple' or 'power harem' where Harry and his harem members combine their powers to overcome great threats. For example, Hermione's intelligence combined with Harry's magical abilities and the unique skills of other harem members like Ginny's Quidditch skills or Luna's intuitive magic.
One common trope is the 'outsider becomes central' where the main character, often an original character in the fanfic, is suddenly in the middle of a group of Hogwarts students who form a sort of harem. For example, a new student from a different magical school might come to Hogwarts and attract the attention of Harry, Ron, Hermione and others in a romantic or platonic way that builds a harem - like dynamic.
There are many HP master harem fanfictions that center around Hermione Granger as well. In some, she might be in a group with other characters from different houses, like Slytherin and Hufflepuff, creating interesting dynamics. These stories often take the existing world of Harry Potter and expand on it with new plotlines based on the harem concept.
One popular trope is the 'alternate universe' where the story takes place in a different setting or with different rules from the original series. For example, a world where Voldemort won. Another is the 'character rewrite' where a character's personality or backstory is changed. And the 'romantic pairing' trope, like Hermione with Draco, which explores relationships that weren't in the original books.
A common trope is power - related. In Harry Potter and Marvel fanfiction, you often see characters either sharing or comparing their powers. For instance, how would Captain America's physical abilities stack up against a wizard's magical skills? Also, the 'found family' trope is there. Characters from both universes coming together to form a new family unit, like some Avengers joining forces with the Hogwarts crew.
One popular trope is the 'crossover' where characters from Charmed and Harry Potter universes interact. For example, the Halliwell sisters might meet Harry, Hermione and Ron. Another is the 'power transfer' trope, like a Charmed one getting some magical ability from the Harry Potter world or vice versa. And the 'hidden relation' trope is also seen, such as a character from one universe being related to a character in the other in some unexpected way.
One popular trope is the 'enemies - to - lovers' where characters who initially dislike each other, like Draco and Hermione, fall in love. Another is the 'forbidden love' trope, for example, a love between a Muggle - born and a pure - blood in a world with so many class differences in the wizarding world. And of course, there's the 'soulmate' trope where two characters are fated to be together.
One popular trope is the 'alternate universe' where the story takes place in a different setting than the original books. For example, a modern muggle world with a hidden wizarding society. Another is the 'time - travel' trope, which allows characters to go back in time and change events. And the 'found family' trope is also common, where characters form deep bonds outside of their biological families.