Well, without knowing what your story's about details-wise, it's kind of hard to come up with really connected titles. But, off the top of my head, I'd suggest the following:
"Giggles in Gotham"
"Dark (K)night of the Feather"
"Going Batty?"
"'Robin' her Sanity" (if it's */f)
If I think of more, I'll post them.