One possible plot twist could be that the other gods oppose their union. Since Ares is the god of war and Athena is the goddess of wisdom, their marriage might disrupt the balance among the gods. The gods might fear that their combined powers would lead to unforeseen consequences. For example, Zeus could be worried that they would become too powerful and try to overthrow him. Another plot twist could be that there's a hidden prophecy related to their marriage. Maybe it was foretold that their union would either save or destroy the world of the gods. This would add a layer of mystery and danger to their relationship.
One possible plot twist could be that the gods oppose the marriage. Since Athena is a virgin goddess in Greek mythology, her getting married would go against the traditional view of the gods. This could lead to a conflict where Percy has to prove himself worthy not only to Athena but also to the other deities.
Perhaps Ino's ex - boyfriend shows up and tries to win her back. This would create a lot of tension as Sai would have to fight for Ino's love and prove that he is the better choice for her. It could also make Ino re - evaluate her feelings for both men.
One plot twist could be that they face opposition from the Soul Society. Since Ichigo is a substitute Soul Reaper and Yoruichi has a complex history there, the elders might try to stop the marriage for political or traditional reasons.
One possible plot twist could be that their families, who initially opposed the marriage, suddenly come around due to an unexpected event. For example, a family member might fall ill and realize how much Mei and Yuzu love each other during the difficult time. Another plot twist could be that there's a misunderstanding that threatens to break up their marriage plans. Maybe someone spreads false rumors about one of them, but they eventually clear it up through honest communication. A third plot twist could be that a long - lost relative shows up and has some strange conditions or secrets related to their union.
A plot twist could be that Ayame is actually part of a prophecy related to Naruto. For example, their marriage is foretold to bring either great prosperity or great disaster to the Hidden Leaf Village. This makes their relationship more than just a love story and puts a lot of pressure on them, as they have to figure out how to fulfill the prophecy in a positive way.
A plot twist could be that Inuyasha is forced to choose between Kagome and saving his friends. Some dark force could put his friends in danger and the only way to save them is to break off his marriage to Kagome. This would create a huge conflict for him as he loves Kagome but also values his friends deeply. Also, Kagome might come from a future where she is suddenly called back and has to find a way to either stay in the past with Inuyasha or go back to her own time, leaving him behind.
Maybe a plot twist is that Jacob has a long - lost relative who shows up just before the wedding. This relative has different ideas about Jacob's future and doesn't approve of his marriage to Renesmee. He tries to persuade Jacob to break off the engagement, which causes a rift between Jacob and Renesmee as they deal with this unexpected interference.
A plot twist might be that Ichigo discovers some long - hidden family secret related to Byakuya during their marriage preparations. This secret could change the way he views Byakuya and their relationship, adding a layer of complexity and drama to the story. For example, it could be related to a past event that involved their ancestors.
Well, it could be that their marriage is part of a grander scheme by the dragons. They might have a hidden agenda that Eragon and Arya are unaware of. For example, the dragons could be using their union to create a new breed of Dragon Riders with special powers. Also, there could be a plot twist where the very act of their marriage causes a rift in the fabric of magic in Alagaësia. This rift could either lead to chaos or a new discovery of magic that no one expected.
One possible plot twist could be that an old enemy resurfaces on their wedding day, threatening to disrupt the ceremony. Maybe a dark guild that Laxus once fought against comes back for revenge. Another twist could be that Lucy discovers a hidden family secret that might change her relationship with Laxus. For example, her family has some sort of connection to Laxus' past that she was unaware of. And a third plot twist could be that a magic spell goes wrong during the wedding, causing everyone to swap personalities for a while, which would lead to some really interesting and comical situations.