Well that was fun...
Its a deep sea mermaid concept thingy
I've done a few of these but they never looked very 'abbysal' imo.
Before you point out her anatomy looks 'off' its intentional
she needs to look long, thin, bony, creepy etc.
(the red things are gills, water goes through the top 4 and out the bottom 4)
*Edit, guys, its has nothing to do with titans. you guys have titans on the brain