have a thing for
To have a strong inexplicable feeling about sth. or somebody.
I have a thing about sweets, for example. If there are no sweets in front of me, I'm not suffering. But if you bring me some, and put it on my desk and I don't eat them, I'll suffer.
Americans definitely have a thing about trains — they try to avoid them.
Lucian has always had always had a thing for lions and when he had the chance to buy one for a pet, from an animal market, he didn’t hesitate.