In some fanfictions, Lucifer could kidnap Chloe as part of a plan to prove a point. For example, he might be trying to show her how vulnerable she is without his protection. This could lead to a series of events where Chloe discovers new aspects of Lucifer's world and her own place in it.
Sometimes other characters from the 'Lucifer' series can also play important roles. For instance, Amenadiel might get involved. He could be trying to stop Lucifer from doing something he believes is wrong, or he might have his own reasons for getting in the middle of the situation. Maze could also be there, either helping Lucifer or Chloe depending on the story's direction.
One interesting plot could be their adjustment to married life while still dealing with the supernatural elements in Lucifer's world. For example, how they handle his devilish powers and the reactions of those around them.
One idea could be that the baby has some sort of special power. Maybe it can see things that others can't, like angels or demons in their true forms. This would add an interesting dynamic as Lucifer and Chloe try to understand and protect their child from the otherworldly forces that might be interested in the baby's power.
Maybe the pregnancy is unexpected, and they initially panic. But then they start to get excited about building a family together. Chloe could start to train Lucifer on how to be a good father, like teaching him about baby care and normal family values, which would be a big change for him since he's from Hell.
Another plotline might involve Shadow being mind - controlled to kidnap Tails. This could lead to a story where Sonic and his friends have to not only rescue Tails but also find a way to break the mind - control on Shadow. In this case, Tails might be able to use his intelligence to try and communicate with Shadow and find a way out from within the captivity.
Another plot might involve Lucifer struggling with his own inner demons when he decides to declare his love. He's afraid that his love for Chloe might put her in danger. So, he tries to push her away at first. But Chloe is persistent and in the end, Lucifer overcomes his fears and declares his love in a very intimate and heartfelt moment.
One interesting plotline could be their eternal struggle for power in a new, alternate universe created within the fanfiction. They might fight not just physically but also in the realm of manipulating other characters' loyalties.
In some fanfictions, there could be a situation where Hermione forms an unexpected bond with Rodolphus. Maybe she starts to understand his backstory and what led him to become a Death Eater. This could lead to a complex relationship where she tries to redeem him in a way. Or perhaps, Rodolphus discovers that Hermione is far more powerful and resourceful than he initially thought, and this throws his plans into chaos as he has to constantly adapt to her actions.
One idea could be that they struggle to balance their work with the upcoming baby. For example, Lucifer's devil - related duties and Chloe's police work. Another could be that they have different ideas about how to raise the child, given their very different backgrounds. Maybe Lucifer wants to raise the child with a more 'devil - may - care' attitude while Chloe is all about discipline and rules.
One idea could be that they face challenges in their relationship due to the pregnancy. Maybe Lucifer is worried about his devilish nature affecting the baby, while Chloe is trying to balance her detective work with the new situation. Another plot could involve them having to protect the unborn child from supernatural threats, as Lucifer's world is full of such things.