A great plot could be that they adopt twins. One is a warlock and the other is a Shadowhunter. This creates a unique dynamic as they have to balance the different needs and cultures of the two children. There could be conflict within the family as some in the Shadowhunter community don't approve of a warlock being raised in a Shadowhunter family. But Alec and Magnus stand firm in their decision and work through the challenges together.
One idea could be that they adopt a young warlock who is having trouble controlling their powers. Alec and Magnus have to teach the child how to manage their magic while also protecting them from those who might want to use the child's power for bad. Another plot could be about adopting a mundane child and introducing them to the Shadow World. It would be full of discovery and the child learning about their new family's unique abilities.
Perhaps a scene where they celebrate Max's birthday. They throw a big party with all of Max's friends. Alec bakes a cake (even if it's a bit lumpy) and Magnus decorates it with his magic. Max blows out the candles, and Alec and Magnus are there, beaming with pride, and it's clear that they are a loving, happy family.
Through the adoption, they might face external challenges like discrimination from certain parts of the Shadowhunter world. This would make them rely on each other more. They could have late - night talks about how to protect the child and in the process, they would share their fears and hopes for the future. This would strengthen their emotional connection and make their relationship more mature. Also, seeing each other as parents could add a new layer of respect and admiration for one another.
One plot idea could be that Magnus and Alec go on a magical adventure together for the first time. They encounter a mysterious magical creature that is causing chaos in the Shadow World. As they work together to solve the problem, their relationship deepens. Another idea is that it's their first time attending a Downworlder - Shadowhunter event together. There they face some prejudice from both sides but their love for each other helps them overcome it. A third plot could be that they have their first real argument and then make up in a very romantic way, exploring more about their different personalities and how they can complement each other.
One interesting plot point could be the development of Alec and Magnus's relationship within the context of the City of Glass. Maybe they face some new challenges together that test their love. Another could be how they interact with the other characters from the original setting in this fan - made story.
One plot idea could be the three of them going on a dangerous magical quest together. They have to face various challenges and in the process, their relationships deepen. Maybe Magnus uses his powerful magic, Alec shows his leadership and combat skills, and Jace his quick thinking.
One idea could be that Alec is really nervous about meeting Magnus' dad. Maybe he tries to learn all about Magnus' family history to make a good impression. He could bring a special gift that has significance in Magnus' family's culture.
One possible plotline could be the challenges they face in dealing with the kid's magical abilities if it has any. For example, the kid might accidentally use magic in inappropriate situations and they have to teach them control.
During the adoption process, they might face some challenges, like dealing with paperwork or the scrutiny of the adoption agency. But through these difficulties, they learn more about each other's strengths and weaknesses. For example, Alec's attention to detail helps with the paperwork, while Magnus's charm helps in dealing with the people at the agency. This makes them respect and love each other more.
One characteristic is the focus on the relationship between Alec and Magnus. It could be their romantic relationship, like in many fanfics where their love story is explored in great detail. Another is the exploration of their individual personalities. For instance, Alec's loyalty and Magnus's magic are often highlighted.
One common way could be through using his magic in a subtle way. For example, he might use magic to create situations where Alec has no choice but to follow his lead. Maybe he makes it seem like the only option for Alec to protect his friends or family is to do what Magnus wants.