The consequences could be various. He might feel a great burden, as if he has to carry the weight of the family's past misfortunes. It could also make him more cautious in life, constantly fearing that the curse will affect his future. For example, if the curse is related to financial ruin, he might be overly hesitant in business decisions.
The discovery of the family curse story could lead to him becoming obsessed with breaking the curse. He'll probably research a lot about it, trying to find any possible loopholes or solutions. This could consume a great deal of his time and energy. He might even consult with various people like historians, spiritual leaders or family elders who might have more information about the curse.
He should first stay calm. Reacting impulsively won't help. He could start by talking to his parents or the eldest family members to get more details.
One possible consequence could be that Draco feels a sense of shock and disbelief. He might initially struggle to process the information. He could then feel a newfound sense of protectiveness towards Ron. After all, in the wizarding world, such a heinous act goes against all notions of respect and safety. Draco might also start to question the people around Ron, wondering how such a thing could have happened without anyone preventing it.
One consequence could be that Bill feels a strong sense of protectiveness towards Harry. He might immediately try to comfort Harry and ensure his safety. For example, he could offer to let Harry stay with him where he can keep an eye on him.
One possible consequence could be a shift in the power dynamics within the village he leaves. His departure might leave a void that could be filled by either positive or negative forces. Also, his friends would likely be deeply affected, feeling a sense of loss and perhaps even betrayal.
Well, Harry might feel betrayed. He could be really angry at Hermione and it might strain their friendship. He might demand an explanation right away.
Socially, it could be difficult for him. If others find out that he still has feelings for Lily and she's pregnant, he could face ridicule or be the subject of gossip. Also, depending on his relationship with Lily's partner, there could be conflict. He may have to face the fact that he has to keep his distance more than ever to avoid causing trouble for Lily and her unborn child.
One consequence could be that Hermione has to face the Malfoy family. They might try to bring her into their way of life, which she has always opposed. It would be a struggle for her to keep her own values intact while dealing with their pure - blood traditions.
There could be a significant breakdown in family relationships. Trust among family members would be severely damaged, leading to a lot of emotional turmoil. For example, the relationship between the son and his parents might become strained as they deal with the disappointment and shock.
Fleur might expose them. If they are students, they could face expulsion from Hogwarts.
One possible consequence is that Harry might face a lot of unwanted attention. People in the fan fiction world could start treating him differently, perhaps with too much pity or excessive curiosity. His privacy would be invaded, and he might feel pressured to conform to the expectations that others now have of him based on what they've learned from the fan fiction.