Imagine Person A of your OTP is an ancient demon (or divine being, if you prefer) and Person B is merely a human. For obvious reasons, they aren’t allowed to act on their feelings or even mention them.
One day Person A decides to shapeshift into a human that they know B will find attractive and try to form a relationship that way.
However, Person B is unaware and rejects the advances as they only love Person A. What happens next is up to you.
Bonus: Person C is a friend/ex lover or fellow love interest of Person A. They are also an ancient demon/divine being and they vow to do everything in their power to destroy B.
any, demon/human
One day Person A decides to shapeshift into a human that they know B will find attractive and try to form a relationship that way.
However, Person B is unaware and rejects the advances as they only love Person A. What happens next is up to you.
Bonus: Person C is a friend/ex lover or fellow love interest of Person A. They are also an ancient demon/divine being and they vow to do everything in their power to destroy B.
http://otpprompts.tumblr.com/post/140077700079/imagine-person-a-of-your-otp-is-an-ancient-demon