One possible plot development could be that the characters initially resist the contract. Harry might be in love with someone else, like Ginny. Hermione could be focused on her studies and not ready for such a commitment. Tonks might be angry about being forced into this situation. But as the story progresses, they start to see the benefits of working together because of the contract.
A plot development could involve a mystery around the origin of the contract. It might turn out that it was created by a dark wizard for some malicious purpose. The three characters then have to figure out how to break the contract while also dealing with their growing feelings for each other. This could lead to a lot of adventure and self - discovery for Harry, Hermione, and Tonks.
Well, in some fanfictions with the 'Harry Hermione Tonks marriage contract', it's a plot device to bring together different story elements. Maybe it was set up by some magical law from the past. It can create a lot of drama. Hermione might be conflicted as she has her own feelings for Harry, and Tonks being involved adds another layer of complication. It can make for some really engaging reading.
Perhaps a plot twist could be related to memory modification. One of them has their memory modified in the past which affects their relationship in the present. For instance, Tonks might have had her memory modified by some dark magic and she forgets her previous relationship with Harry and Hermione. As they try to restore her memory, they discover secrets about their past together and it changes the course of their marriage.
One popular 'Harry and Hermione marriage contract' fanfiction is 'The Contract' which delves deep into how they navigate their new relationship status within the wizarding world. It has a great plot that combines elements of mystery and romance.
Well, it could involve them initially struggling with the idea of the marriage contract. Maybe Harry is hesitant because he has his own plans and Daphne might be a bit snobbish at first. But as they spend time together, they start to see the good in each other.
One idea could be the cultural and family clashes that come with such a contract. Maybe Harry's friends are shocked and have mixed reactions. Another could be how Harry and Tonks grow to understand and care for each other in the context of this contract. For example, they start off as strangers in this arranged - like situation but gradually find common interests.
One possible plot development is that Hermione and Viktor try to find a loophole in the marriage law. They might team up with their friends, like Harry and Hermione's Gryffindor pals, to research old magical laws and precedents. Another is that they could pretend to be in love to avoid the consequences of the law at first, but then actually fall for each other during the charade. Or perhaps Viktor's family in Durmstrang has some influence on the situation, either trying to push the marriage or prevent it depending on their own interests.
One common theme is the exploration of their relationship. Since they were friends in the original series, the marriage contract forces them to see each other in a different way. Another theme is the reaction of their friends. Ron, for example, might be jealous or confused. Also, dealing with the wizarding society's expectations is a theme. In a world where pureblood traditions still hold some sway, a marriage contract can bring up issues of class and family honor.
One possible plot development could be that Dark Harry has some ulterior motive for kidnapping Hermione. Maybe he wants to use her knowledge to further his dark plans. For example, Hermione is known for her intelligence and vast knowledge of magic, and Dark Harry might force her to help him find a powerful and dark magical artifact.
Another plot aspect could be the discovery of the origin of the marriage contract. It might be a part of some ancient magical family pact that was long forgotten. As they dig deeper into the history behind it, they not only learn more about their families but also about themselves. This journey of discovery can strengthen their bond and make them more committed to making the marriage work.
One possible plot development could be the initial shock and confusion for both Harry and Hermione. They would have to deal with the reactions of their friends, like Ron, who might be very surprised or even a bit jealous. Then they'd need to figure out how to balance their new situation with their fight against Voldemort or other magical threats. Another aspect could be how they prepare for the baby, from finding a safe place to live to getting all the necessary baby supplies in the wizarding world.