For The Lady and Her Hound I would say my top three influences were:
1) Bloodborne
I just love the victorian gothic setting and fashion! Plus monsters and eldritch horrors?? Y E S. I also love how the story was told through the worldbuilding and how you had to piece together what happened in the past.
2) Canticle For Leibowitz
Canticle For Leibowitz is an old sci-fi novel. I first read it because my partner recommended it to me when I was stuck on finding good books. I really fell in love with how you found out about the new state of the world, post nuclear apocalypse through the experiences of the characters. I also really liked how the main characters were monks trying to preserve the knowledge from the before times. I'm sure there are more novels out there that explore the 'end of the world' and how people live centuries after the event - but it's not something I've found a ton of, so I really loved that about Canticle for Leibowitz.
3) Places in Ireland, Scotland, Wales and England
I really love the old castles, towns and villages! And the architecture!