I feel ashamed that I really just dropped my link in a bunch of these normal promo threads in the beginning. I saw others doing that and thought "okay, seems like the way they do it here. Seems... pointless, but who am I to say that.".
But I really like this approach here!
I'm... super bad at self-promo, but I'll try my best. 
Should be a piece of cake...
Here we go
- Take some super overdone clichès:
Good vs. evil, angels vs. demons
A damsel in distress
A hot guy with a fortress and countless servants
Power imbalance
A romance against all odds, enemies to lovers
- Season it with:
Some more fantasy elements
A certain darkness
Grown-ups (get the stuff that's a bit more aged, like 30+)
Some action
Some of the other action
- Stir it and make sure that the large chunks are crushed. New, more complex flavours should spark as a result:
There is no black and white, only gray in different nuances
This "damsel" can and will fight back hard
Didn't you know that fire burns? And no pampering in sight...
Power is a question of circumstances and perspective
Love doesn't fix anything miraculously, relationships are hard work
-The consistency should be chewy but not fall apart. Enjoy in slow pace
Sooo, I hope you get where we're going. 
If you enjoy diving into darker topics, a harsher world, into the despair of being an angel imprisoned by a demon, well, I have something for you.
There won't be much horror- or gore-like elements, but you can expect a lot of other heavy, maybe even disturbing stuff. I'm not fond of adding drama for dramas sake. And it's also just not necessary... cause there're a lot of bad things happening anyways. Just because the world is like it is.
But this story is not a feast of darkness, there's always a bit of hope, a ray of light.
Cause... why going on, when it's all doomed from the beginning?
So, romance and love are there. But they're not easy.
It's all a question of the decicions made. What is one willing to fight for? And how much is one willing to pay...
A bit related art (drawn by me):


For more infos please take a look at the description. 
Read with care; 18+/ mature
EN (I translate it myself, so it won't be perfect
)
DE/ GER