Well, obviously Danny Denton himself is a common character. Then there might be a female lead who is strong - willed and becomes an important part of his harem early on. There could also be a sidekick type of character who helps Danny manage his harem affairs.
Another possible fanfiction is 'The Formation of Danny Denton's Harem'. It could detail how Danny gradually meets and forms relationships with the members of his harem, perhaps starting from chance encounters and evolving into deeper emotional connections.
Danny himself is obviously a common character as the center of the harem. Sam and Tucker are often included as well, with Sam sometimes being part of the harem or at least a key figure in Danny's life in the fanfiction. There are also various female ghost characters like Ember or Kitty who are frequently added to the harem due to their interactions with Danny in the original show.
Obviously Danny Phantom himself is a central character. Then, Sam and Tucker often appear as his friends who might have to deal with the whole harem situation. Among the ghostly harem members, characters like Ember McLain are quite common. She has her own charm and powers which make her an interesting addition to the harem concept in fanfiction.
Sam Manson could be one of the characters in the harem. She's already a close friend of Danny's in the original series, and in fanfiction, their relationship could be developed further into a more romantic or complex one. Tucker Foley might also be included in a different kind of relationship dynamic within the harem. He could be Danny's best friend and also have a unique bond with the other harem members. Valerie Gray is another potential character. She has a history with Danny and her addition to the harem could add a lot of interesting storylines, like her struggle between her hunter instincts and her feelings for Danny.
Well, for the Danny Phantom side, Sam and Tucker could be involved. Sam might be jealous at first when other girls start showing interest in Danny. Tucker could be the one giving Danny advice on how to handle the harem situation. From other shows, if it's a crossover with a magical girl anime, characters like Sailor Moon could be part of the harem. Her kind and powerful nature would make an interesting dynamic with Danny. Another could be Kim Possible. She's a strong and capable girl who would likely be intrigued by Danny's powers and get involved in his adventures, and potentially develop feelings for him.
Obviously, Peter Parker is a common character as he is the central figure in the Spiderman universe. Mary Jane Watson is often included in the harem as she has a long - standing relationship with Peter in the original comics. Gwen Stacy might also be part of it, given her importance in Peter's life.
Besides the main female characters from the original series, some fanfictions also include Tenten. She brings her weapon - master skills and a no - nonsense attitude to the harem. Another character that might show up is Temari. Her strong - willed and independent nature from the Sand Village can create interesting interactions within the harem. And then there's also Anko Mitarashi, who has her own unique charm and can be a wild card in the Naruto harem fanfiction.
Well, of course, Godzilla himself is the central character. And often, there are other kaiju like Mothra who could be part of the harem. She has a long - standing relationship with Godzilla in the Godzilla lore and can be a likely candidate in the harem fanfiction.
Other characters like Kakashi or Jiraiya could potentially be part of the harem in some fanfictions. Their unique personalities would bring different elements to the story. Kakashi's cool and mysterious nature or Jiraiya's more carefree and perceptive self could interact with Kushina and the rest of the harem in various ways.
Common characters in Danny Phantom group chat fanfiction include Danny, who is central to all the action. Sam, who is Danny's friend and often has strong opinions on environmental and ethical issues related to the ghost - fighting. Tucker, the tech - geek friend who can provide all sorts of technical solutions. And of course, Vlad Masters might also make an appearance in some fanfictions. He could be trying to infiltrate the group chat to gain information on Danny or to cause trouble for him. And let's not forget the ghosts like Skulker or Ember, who could potentially interact with the group chat in some supernatural way.