Another plotline could revolve around the cultural differences between Alec and Magnus that come into play while raising the kid. Magnus, with his warlock heritage, might have different ideas about things like education or discipline compared to Alec, who is from a more traditional Shadowhunter background. This could lead to both comical and heartwarming moments as they navigate through these differences.
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.
Obviously, Alec and Magnus are the main characters. Alec is a Shadowhunter, known for his loyalty and his growth from a more reserved person to someone more open - minded. Magnus is a powerful warlock, flamboyant and full of magic and mystery.
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.
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.
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.
Another plotline might be that in a world where the laws of nature are different for certain characters, Magnus and Alec decide to have a child in this unique way. The story could then focus on how they deal with the reactions of their friends and family, and also the challenges of Alec's pregnancy, like his changing body and emotions. It could also involve them preparing for the arrival of the baby, from choosing a name to setting up a nursery.
Love is a very common theme. Their relationship, which is between a Shadowhunter and a warlock, is full of challenges and the fanfics often explore how they overcome these through love. Another theme is acceptance. Alec has to accept Magnus's different lifestyle as a warlock, and Magnus has to accept Alec's duties as a Shadowhunter.
One popular theme is the first kiss. Writers often explore the nervousness and anticipation of Alec and Magnus before their first kiss. It could be set in a romantic location like on a rooftop under the stars.
There are several fanfics worth checking out. For example, 'A New Beginning for Alec and Magnus' which is about them starting a new chapter in their lives. In this fanfic, they face new challenges and grow even closer as a result. Some fanfics also explore their powers in unique ways, like 'Alec and Magnus: Powers United' which shows how their combined powers can be used to save their world from a great threat.
Love and acceptance are big themes. In many fanfics, Alec has to come to terms with his feelings for Magnus, a warlock, which goes against what he has been taught as a Shadowhunter. Also, there is the theme of sacrifice. Sometimes one of them has to sacrifice something for the other's safety or well - being, which really shows the depth of their love.