So where to start? I guess I start with the hair? as it's one of the hardest things to explain for me.

The hair is cut straight but it's messy because shes kind of a messy person. The hair is tight up at the back but not all of the hair and I think I should change the bangs to be as long as the rest of the hair but I had problems drawing them anyway. Even so she probably look better with lighter hair I ones again have to go with the darker one because if her hair wasn't blue it would be black.

She's wearing a Blue hoddy which is meant to have a underwater design of some type but I can't figure it out sadly T^T the hoddy is lighter then the Hair.
Shes also wearing a knee long blue skirt that's darker then the hoddy, Idk if it's lighter or darker then the hair yet.
Shes also wearing rainy/rubber boots for some reason which are also blue like the hoddy.
And even so this should be irrelevant shes not wearing socks nor panty's...

Her skin is a every light grey blueish color and the legs are fully covered in scales that looks like pants. They turn black/dark at the end of it like her fish tail as it is her fish tail just turned into two legs.
She might have some scars from in the water. Ether from other beings in the water or trash in the water from the human culture.

Eyes blue with some red in it, pupil is a thick slit that get's thinner at night or with hunger.
The teeth are based of VampireFish and Bats teeths
The ears should be hiddin with the hair but idk how to that because of the way I drew the ears trying to make it a mix of bat ears and fish fin.

I'm so sorry for the amount of text ^^" I seem to be unable to explain her design in short TwT

Anyway I post this as my #ArtWeeklies Submission and #ArtFight character Profile
https://artfight.net/character/5467770.marliria-tsuru

Maybe art of her can help me draw her better..