Watery Bowel Movement

Ok. I wasn't able to find a more graphic picture, but this one suggests what I was aiming for. "The Ghost" is far from the greatest horror movie you'll ever see, but it has its good scenes here and there. I will ignore the film's plot (basically a girl with amnesia who did something terrible, or so we think) and jump to the very beginning, which is one of the only parts worth telling (ironically, I fail to see its connection with the rest of the movie).
A group of girls having fun in a loud slumber party decide to contact spirits to spice up the night. When the sister interrupts the game, the girls go to sleep without ending the contact properly. In the middle of the night, when everyone is asleep, the annoyed sister appears in the kitchen, buckets of water emanating from her small mouth. It's not until she's drenched and about to pass out that hair starts to flow from her lips. Not much is said about the character later on, but I'm pretty sure she didn't make it.