The Garden at the End of the World?
Thank you very much for asking because this is my favorite original idea.
Our story starts with a girl visiting her aunt. The aunt lives in a manor in the countryside and even though everything is perfectly polished - from the garden, to the dining room - some things are not as they should be.
When she blinks, she can almost see the rotting walls. In the shadows, there are always whispers of dark and forgotten things. And in the garden - well, her aunt never lets her go unattended.
In the garden, the girl thinks there might be a gateway to somewhere darker. A place you can't really ever get out of, but souls do try.
And then, of course, there is the man in a three-piece suit that sometimes comes to visit.
Essentially, it is a gothic/horror story about two sisters and a curse. One of them got freedom. The other stayed in a violent family's violent house, making sure that nothing - and no one - who should be on the other side of the door ever passes through.
I'll leave you with a snap of my Pinterest board: