I usually get story ideas from my dreams. Matter of fact, IH came from a dream. So did BMO (the ms I'm currently writing), an unfinished time travel, and a new idea I'm currently storyboarding.
But this takes the cake.
I had an odd dream last night. I won't bore you with all the details, except to say the darned thing was a head-scratcher all around. However, the thing that has me confused were these weird little bulldog bats. They seemed to hang out (no pun intended) on a web in the corner of the back patio of a private school. They had blue mouths, inside and out, dripping blue saliva or blood or something. They were literally little bulldogs (barking and whining ones) with large black bat wings.
I'm sure you can understand why I won't even bother to try to analyze this one. I suppose my subconscious mind thought I needed a major WTF? moment.