A Cover Design for the Novel I'm Writing

Yup, I'm writing a novel.
And no, I'm not even dreaming of ever getting it published, since I'm a complete novice and my stories tend to suck big time.
I'm doing it only as a hobby.
Period.

That being said, let's get started.
The title is in Finnish (since it's my mother-tongue) and it translates into something along the lines of 'Licad And The Underwater Kingdom'.
As the title suggests, it's a fantasy novel.
The story is a mix of supernatural and historical elements with some Slavic folklore blended in, although it doesn't take place in any known country.

Licad (The 'c' is pronounced the same way as in Marco) is the name of the main character, and as you can guess, she is the red headed girl on the cover. 
The word comes from turning backwards the name of an ancient Guanche princess, Dacil.
The other characters' names follow the same, inverted pattern. (For example, Ecila = Alice.)
The second main character is called Nagol. He is a mythological water spirit, the Vodyanoy, also known as 'Vetehinen' in Finnish.
I came up with his character design myself, and decided to emphasis the fact that he's half fish by making his ears look like fins.
Without further ado, Here comes the sypopsis of the story:

Licad is a young girl living on a remote island, in a small fisher village with her foster parents.
The village used to be quite prosperous, but was impoverished due to over-fishing. Nowadays the whole island is tortured by hunger, since the unpredictable ocean climate makes farming almost impossible.
The superstitious villagers blame their hunger on bigger forces. The villagers were sure that they had angered the great Vodyanoy, the water spirit.
For centuries people had sacrificed bread, tobacco and fish for the Vodyanoy. But now, when the whole island was starving, confused and scared, people were beginning to consider sacrificing something more valuable.
A human.

The islands most influential person, an old woman called Ecila who was known to be able to converse with the spirits of nature, saw a dream.
A dream in which the Vodyanoy himself addressed her, revealing the old woman his wishes.
The water spirit wanted a human sacrifice, a virgin with eyes like gold and hair like fire.
On the island, where the aforementioned traits were very uncommon, one unsuspecting girl fitted the description; Licad.

Ecila decided to fulfill the Vodyanoyd's request, despite of the resistance from the girl's parents, in the hopes of saving the village from starvation and death.
'One life from the lives of hundreds of islanders', were the words which, in the end, forced Licad's parents give up their daughter.
The poor girl was imprisoned, cleansed with purifying water and clothed with sacrificial robes.
Licad was delivered to the open sea on a small boat, and when they were far enough, she was cast over the edge on the icy water, escorted by prayers.
With her hands and feet bound, the girl was left drowning with no chance of survival.

Instead of finding herself in the afterlife, Licad had ended up on a completely different place: she woke up on a colorful room, in a soft bed surrounded by pillows, staring eye-to-eye on a creature which was half human, half fish.
Licad had arrived into the underwater palace of the Vodyanoy himself.
And he wasn't going to let her return.

I left out some parts, but the plot should be more or less understandable.
What do you think?
Is the idea completely ridiculous?
Tell me on the comments.