It could have a negative impact. It might change the perception of the beloved characters in a way that is not in line with the original. For example, if Harry Potter is depicted as smoking, it goes against his innocent and heroic image in the original series.
The 'Harry Potter' fandom is huge and diverse. But fanfiction about drinking and smoking can introduce elements that are not in harmony with the main themes of the series. It may lead to a distortion of the values that the series represents. Young fans who look up to the characters might be confused or influenced in a negative way. Also, it could make the fandom seem less family - friendly, which was one of the main attractions of the original 'Harry Potter' series.
One possible impact is that it can divide the fandom. Some fans who love the original relationship between Harry and Hermione might be put off by such fanfiction. On the other hand, it can also attract new fans who are interested in seeing this new take on the characters.
It can divide the fandom. Some fans might be open to new interpretations like Harry as a 'bad boy' and enjoy the creativity, while others who are purists might be very much against it. This can lead to arguments and a split in the community.
It could potentially damage the reputation of the fandom. Since the Harry Potter series is so popular and has a large and diverse fan base, including many young fans, the existence of such extreme and inappropriate fanfic might give outsiders a wrong impression of what the fandom is about.
It can alienate a large portion of the fandom. Since the Harry Potter series has a broad audience including many young fans, sexy fanfiction can make them feel uncomfortable or excluded. It also may distort the original image of the story and characters.
It gives the fandom a bad reputation. The 'Harry Potter' series has a global following and is associated with positive things. Fanfiction like this makes the whole fandom seem seedy and inappropriate, which is unfair to the vast majority of fans who engage in positive and respectful fan activities, such as creating art, writing proper fanfiction about the characters' adventures or relationships within the appropriate context of the story.
It can turn away many fans, especially those who want to keep the purity of the 'Harry Potter' world. When such vulgar fanfiction exists, it makes people feel that the fandom is not a positive and clean place anymore. This kind of content also goes against the values that the original series promotes, like friendship, courage and love. And it might make some people, especially parents, reluctant to let their children be part of the 'Harry Potter' fandom.
Most likely not. The 'Harry Potter' series is aimed at a young audience and the concepts of drinking and smoking go against the family - friendly nature of the original work. Fanfiction that involves such themes might deviate from the positive values that the official series promotes.
Another possibility is that it's used to age him up or make him seem more worldly. Smoking can give the impression of a character who has experienced more of life. In fanfiction, if the writer wants to explore a more mature Harry Potter, having him smoke could be one way to visually and thematically represent that maturity. It could also be part of a character arc where he starts smoking and then realizes the negative impacts and tries to quit, showing growth.
It can harm the fandom's reputation. The 'Harry Potter' fandom is known for its creativity and positive engagement with the series. Fanfiction with inappropriate content like this can make the fandom seem less family - friendly and more focused on adult or disturbing themes, which may drive away some fans, especially those who are fans because of the original positive values of the series.
One negative impact is that it may drive away younger fans. Since 'Harry Potter' has a large base of young fans, when they encounter such sexualized fanfiction, it might make them feel uncomfortable or even disgusted, causing them to distance themselves from the fandom. Also, it can make the fandom seem less family - friendly, which was one of the main attractions of the original series.