So for anyone who has watched demon slayer, I'm pretty sure you know how this universe will work. But just in case, I'll give a quick rundown.

To make it short and simple: Demons exist, and they eat humans to survive. The only things that can kill them are sunlight, and being beheaded by a specific metal made into a blade. There are demon slayers who work in a secret organization who travel the world and kill these demons to keep everyone safe.

Some extra details (some that I edited to make this thing easier) include:

•If a specific type of demon gives their blood to a human (or forces it into them), that human will become a demon. This is how they multiply.

•That being said, a good majority of demons were all human at some point. There are hardly any demons who were born demons.

•A lot of demons all have some sort of power or magic

•There are a few demons who don't attack humans, and instead try to help them, and try to find a cure that will turn demons back into humans

And now for the scenarios:

A) (Oc/character) was going to visit (crush/best friend), only to discover they're a demon now! But they seem to have some sort of self control, and refuse to attack (Oc/character). Now, (Crush/best friend) is training to become a demon slayer, so they can interact with demons and try to find a cure for (Crush/best friend).

B) Scenario A but the roles are switched. (Oc/character) Is the human-turned-demon, and (Crush/best friend) is trying to find a cure.

C) (Oc/crush) Is traveling to their next destination, but the thing is they're severally injured from their last fight. They are found by (Crush/best friend), who is a demon, but are working to heal humans and find a cure for demons. They take them in and help them get into better shape before they start traveling again. How will this go? (Again, roles can be switched)

D) Any other scenario you want. The last three were just the ones I could think of off the top of my head