Cordelia is a mermaid that lives in the sea (where else would they live?), she is often referred to as a sea jewel, as her name means 'a sea jewel'.

Have you ever wondered what caused the old sailors in fairy tales to crash? Even when there wasn't a storm coming? Well it was Cordelia. She could make the sea have a storm with a flick of her finger, now remember, now all mermaids are good, some of them are actually quite evil, but no one knows if Cordelia was a good mermaid, or a bad one. Sre she caused the occasional storm, and lured young men that were steering the ship to crash with just her voice. But she also liked the seas and ocean to be clean, so she everyday she'd swim out, and collect everything from dryland, and dispose of it.

Everyone knows the Titanic right, and how it went down? (Of course everyone knows the old story) But do you really?
Here's how it actually went:

It was April 15, 1912, when Cordelia sank the Titanic.
She was so sick of the humans polluting the water, with their big ships and all that, so she decided to take action, and show them that this was still her ocean.At first, she heard of 'The Unsinkable Titantic', and thought it wasn't true, so at first she tried to get rid of some other ships, with her icebergs, but that failed, so when she started to hear The Titanic, she knew what she had to do. She used her sea powers and created an iceberg, straight infront of the boat at the last second, leaving the boat no time to turn, as it was to heavy and big to move in just a short amount of time. She felt bad for everyone aboard, but she knew it was the right thing to do, in a twisted way. 
Now everyone knows what happend, so let me sum it up: Everyone on the boat died,with only a few living.
End of story.

As you can tell, she was a twisted person, but is Cordelia still with us today? If so, I hope she doesn't know of all of our pulloting, or else we might have a Titanic #2 happening, what if she got rid of the Internet?!?!