The Black Beauty Sisters is Sheshe and Mimi. Sheshe is the one dressed in red and Mimi is the one dressed in blue. These two are not part of the Dark Lovers, but instead they were transformed from angler fish by Gaito. This is because Gaito was tired of the Dark Lover's constant failures. The Black Beauty Sisters have the power to sing and overpower the Mermaid Princesses.
Mimi:Hi!My name's Mimi! Sheshe:And im Sheshe.We often try to defeat the Mermaid princesses,but it never works,even though we have the power of hell.Our two songs are:Voice in the dark. Mimi:And Yami no baroque!
Voice in the dark(english):
Voice in the Dark!
The ~Melody~ of Darkness 
that steals the bonds between your pearls.
Voice in the Dark!
Now! Let"s begin magnificently beautiful show!
Voice in the Dark!
Our song is brought forth
with the echo of the power of darkness!
Peace is nothing more but an illusion
falsely reflected off the surface of a mirror.
A string made of waves entwines around one another bundling, and becomes a tide.
The demonic energies in our hearts change into a prank-filled vigor.
Surely, it would bewilder those who are weaker than us.
Voice in the Dark!
A black wave gently plays this melody we sing.
Voice in the Dark!
It stops all love, and becomes a chain with no shape
That eddy"s about you, within this refrain.
and steals the bonds between your pearls.
Throw away these "feelings" you have.
They"re nothing more but a soliloquy that a dreaming
girl would shout out, that reaches no one but themselves.
Voice in the Dark!
Now! Let"s begin magnificently beautiful show!
Voice in the Dark!
Our song is brought forth
with the echo of the power of darkness!
The happy people who think they can protect their love
believe too much in their "communication" and are blinded by such.
Voice in the Dark!
A black wave gently plays this melody we sing.
Voice in the Dark!
It stops all love, and becomes a chain with no shape
Voice in the Dark!
Now! Let"s begin magnificently beautiful show!
Voice in the Dark!
Our song is brought forth
with the echo of the power of darkness! 
The heart-shattering dark ~Melody~...
Becoming fiercer, stronger, and hotter...
Eddying about you, within this refrain...
This heart-shattering dark ~Melody~...
Yami no Baroque(english):
A baroque that shuts away light becomes beautiful noise.
The whisper of our dark trap cradles you. Sleep forever.
Slowly waking up
are the shadows of our hearts.
The roses of the deep sea become decorations, forcing pearls to freeze over.
Now, together with all of you, your wishes become one.
We devote ourselves to the great darkness.
The heart-stealing baroque embraces a wave of negative energy.
The world you believed in vanishes in an instant without a sound.
Let"s celebrate the time where everything will end
as it slowly heads this way.
Praise an icy smile, and turn pearls to ash. 
Ah my friends. If you have this light of hopes,
then that"s just a homage to the despair oozing out from it.
A baroque that shuts away light becomes beautiful noise.
The whisper of our dark trap cradles you. Sleep forever.
A paradise sealed away...
Now, together with all of you, your wishes become one.
We devote ourselves to the great darkness.
In a completely changed world, you can understand just how fragile fate is.
Before the hopeless sadness crushes your heart.
A baroque that shuts away light becomes beautiful noise.
Together with us, head towards t
he future whispered of in our dark trap...
