This prompt is based off some characters I created for some stories of mine. They are, in the grand theme of things, rather minor characters. The series they are in defines demons as basically being basically another race of beings from humans that are generally, but not always, able to think and communicate similarly to humans. As you can obviously tell from the prompt, they are similar enough to humans to be able to have children with them.
In my specific story, these twins are two of three offspring for their parents. They are adult males in their fifties and their younger sister is around the same, probably. She hasn’t really come up yet. The sister is half human, half demon, which is the much more common way of these things turning out. The twins split this not because they are twins, but because the father’s demonic powers pass on in a very specific way and the oldest was always going to be 100% demonic. Since he had a twin, that did influence his brother, but the older twin being demonic was not because of being a twin.
As is always the case, you don’t have to base what you do off what I did, but to let you know, the human twin married and had two daughters, twins like their dad. The girls spend some time with their cousins at an event and turns out the main act is their uncle, their dad’s twin. The girls do know this before hand, but hadn’t told their cousins because they hadn’t seen a reason to and just didn’t think of it. On top of that they’ve never been to this kind of event before, so don’t know what to expect and their uncle uses magic on the crowd.
I won’t go into much more detail than that, but their uncle has definitely caused problems for the family their mom’s brother married into, not so much their dad’s actual in-laws, but for his in-laws’ in-laws. That just seemed like a bit much to put on the prompt and in a bit more restrictive. Although I don’t really use these characters much, I find them a lot of fun and I hope you are able to find something you want to do with this prompt. What kind of problems would you have happen between the twins? And what kind of relationship would you give them outside of this?