Jervis Tetch, aka The Mad Hatter in Batman’s crime files, Gossip Gertie at the Iceberg Lounge.
Jervis’s most memorable appearance involved his Aunt Maud coming to Gotham. Auntie didn’t know he was a criminal and Jervis didn’t want her to find out. Zany hijinx ensued.
More recently in Comedy of Errors we saw inside his lair:
It wasn’t even the chess piece furniture that bothered Oswald, it was how… nice everything was. Meticulously clean, small and dainty ornaments arranged neatly in rows on the mantelpiece or in little groupings on the end tables, the whole place smelling faintly of blueberry jam… When all was said and done, it was a lot creepier than Jonathan Crane’s. The Scarecrow had skulls covered in corn husks hanging off little hooks. This place smelled like blueberry jam. It conjured images of some sweet old lady’s cabin you come upon in a childhood fairytale when you’re lost in the woods. She invites you in, since it’ll be getting dark soon, and has some homemade cookies just coming out of the oven. Before you know where you are, she’s after you with a hatchet wanting to bake you into a pie.