I'm not sure of a specific 'bad dog harry potter fanfiction' off - hand. But it could be that the 'bad dog' is a familiar of a dark wizard in the fanfiction world. This dog could be causing trouble around the wizarding world, stealing magic items or causing mischief in Diagon Alley. Or perhaps it's a dog that has been experimented on by some rogue wizards and has developed strange and dangerous powers that Harry and his friends have to deal with.
Well, one 'bad dog' - themed Harry Potter fanfiction could be about a stray dog that wanders into Hogwarts and causes chaos among the students. Maybe it has some sort of magical ability that it doesn't understand, like being able to turn invisible briefly when it's scared. Another could be a story where Harry Potter befriends a dog that is actually a cursed wizard, and he has to find a way to break the curse. And there might be a fanfic where a dog is used as a distraction by the Death Eaters during a battle at Hogwarts.
There is 'Dog at Hogwarts' which is quite interesting. It follows a dog's journey through the halls of Hogwarts, making friends with the students and getting into all sorts of magical mischief. It combines the charm of dogs with the magic of the Harry Potter world in a really fun way.
One popular 'Harry Potter guide dog' fanfiction might be 'The Guide Dog of Hogwarts'. It could feature a dog that helps a character, perhaps a disabled student, navigate the halls of Hogwarts. The dog could have some magical abilities or just be an ordinary dog with extraordinary loyalty.
There's a fanfiction called 'A Dog's Perspective on Hogwarts'. This one is really interesting as it tells the story of Hogwarts from the point of view of a stray dog that somehow finds its way into the school grounds and experiences all the magic and mystery there. It gives a whole new look at the familiar Hogwarts environment.
I don't have a particular fanfiction to recommend. However, when you search on platforms like Wattpad, make sure to read the reviews and summaries. Look for ones that seem to have a well - thought - out plot regarding Harry as a dog animagus. Maybe start with the ones that have high ratings and a lot of views. That way, you're more likely to find a good quality fanfiction about this concept.
Another one is 'A Dog's Perspective'. This fanfiction gives a really different take on the 'Harry Potter' world by showing events through the eyes of a dog Animagus. It delves into the relationships between the characters from this new point of view. It's quite long and detailed, which makes it a great choice for those who want to really immerse themselves in the concept of a dog Animagus in the 'Harry Potter' universe. There are detailed descriptions of how the dog Animagus experiences magic, and how it copes with the often - complex social situations in Hogwarts.
One 'harry potter dog demon fanfiction' could be about a dog demon that somehow gets involved in the wizarding world of Harry Potter. Maybe it's a guardian for Harry, using its demon powers in a unique way to protect him from the Dark Arts. However, it's not easy to find specific ones just like that. You can try searching on some popular fanfiction websites like FanFiction.net or Archive of Our Own.
One common plot element could be the dog causing disruption. For example, it might run amok in Hogwarts, knocking over potions and scaring first - year students. Another could be the dog having a hidden power or connection to the wizarding world's secrets. Maybe it's the key to unlocking an ancient spell or a hidden chamber. And often, the main characters like Harry Potter would have to either tame the dog or figure out its mystery.
Finding a fanfiction specifically about Harry Potter having a fairy dog can be a bit of a challenge. Fanfiction is a very diverse world, and while there are countless stories about Harry Potter, the ones with this particular element might be scarce. However, you could try to write your own. Imagine how the fairy dog could interact with Harry's magical world. It could have special powers that help Harry in his adventures at Hogwarts. You could even create a whole new story arc around this fairy dog and Harry's relationship with it.
There are quite a few fanfics out there. One way to find them is to check on fanfiction.net or Archive of Our Own (AO3). Just search for 'Hetalia Black Dog Harry Potter' on their search bars and you'll likely get a list of relevant fanfics.
I'm not sure specifically which 'harry is female dog' fanfiction is good. You could try searching on popular fanfiction websites like Archive of Our Own or Fanfiction.net.