Shoko

The Ghost Lady appears in "The Creeps" when Finn thinks he's the last one "alive", and hides in a room in the Castle. Suddenly the Ghost Lady IT CREEPED ME OUTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTT The Ghost Lady has light greyish-blue skin with scale-like lumps and long, green seaweed-like hair. Her neck is unusually long. Her scales are light blue, her irises are black, and her pupils shine red. Interestingly, her appearence differs from the most of the other Ghosts in the series, who are all less colorful and more smoothly shaped.

In The Ghost Lady's castle, just before the top floor there is a picture of a blue-ish green woman with long orange hair hugging a mutant bull. The woman in the picture bares a huge resemblance to Ghost Lady and could have very well been her when she was living. If this is true, it is possible that she will have a larger role in the series later on.

Abilities
The Ghost Lady phased through a wall, which was preceded by a ripple effect on the space and a humming sound. Her green hair grew to fill the library that Finn was hiding in, as if trying to reach him. The tides were rising and hitting the castle hard when Finn was on the top floor. This could have been her doing as either a ghost power of the ocean or a ghost power of fears (since Finn is afraid of the ocean). She was also able to tear holes through the floorboarding, move a chair, and summon crows from a painting while either offscreen or invisible(orTTTTTTTTTTTTTTTTTTTTTTTTTT that there were other ghosts in the house that were responsible).