Hawkmoth's character development in the 'hawkmoth gets help from a guied fanfiction' could vary. Initially, he's all about his evil plans. But with the guide's help, he could become more empathetic. For instance, the guide might show him the consequences of his actions on the people of Paris. This could make him hesitate in his villainous deeds. He may also start to adapt new skills or knowledge from the guide, which could change his modus operandi. This new influence could make him a more three - dimensional character, with a mix of his original villainous traits and some new elements introduced by the guide.
It could be a character from a different dimension or realm. This character might have some sort of connection to the Miraculouses and sees potential in Hawkmoth. They decide to help him, thinking that they can redirect his actions towards a more positive outcome, or at least a less destructive one.
Well, in some fanfictions, Hawkmoth might use false promises. He could promise Cat Noir something like the power to save a loved one in exchange for his help.
I'm not sure specifically as I haven't read this particular fanfiction. But the guide could be someone with special powers or knowledge. Maybe Hawkmoth gets help like strategic advice or some form of magical assistance to further his evil plans.
On a personal level for Adrien, he would be straying from his own moral compass. He has always been a character associated with good and helping others. By helping Hawkmoth, he would be going against his own values, which could lead to internal conflict and a possible downward spiral in his character development. He might start to question his own identity and the choices he has made, and it could take a lot of effort to get back on the right track.
They could offer him information. Goblins often have a deep knowledge of the magical world's history and secrets, which might be crucial for Harry's journey. For example, they might know about some hidden enemies or undiscovered spells. They could also give him advice on how to deal with certain magical creatures or situations that he is unfamiliar with.