"Mota mota no injigo kasumi, kyuaa Misuto!"
"The slow indigo mist, Cure Mist!"
Indigo Kasuko is a mature and sophisticated, but tough 17 year old girl. She lives alone now, because her parents are divorced and she doesn't like that, so she ran away with their money.
Kasuko's hair is violet blue, some tied in a side tail with two hairclips. Her eyes are navy blue. She wears a blue-violet dress, and a pair of black shoes. Her school uniform is similliar with the Middle School, but the sleeves and the skirt are longer. The ribbon on her chest is also smaller.
As Cure Mist, her hair is now white and longer. She wears two wavy hairclips on her hair. On her chest is a blue ribbon with her Rainbow Palette on it.The top is white with transparent indigo shoulder pads. She wears indigo sleeves similliar to Rosetta's. Her bottom is a knee length electric-indigo skirt. She wears a pair of indigo boots with a rainbow heart on each of it.
Kasuko opens her Rainbow Palette,spins its dial,then waves her hand in front of it. She then says 'Pretty Cure, Rainbow Stone Power!',then she is covered in blue light. First her top appears. A stream of indigo water covered her hair, then it turns into mist. Kasuko's hair changes, then her hairclips appear. Mist covers her hands, making her sleeves to appear. Her boots appear,she then catches the Rainbow Palette that was falling,then put it in her chest, making her ribbon to appear.She introduces herself while striking a pose. (One hand in her hair and the other one on her hips.)
Creates an illusion to make the enemy dizzy
Creates a wall to defend from attacks.
Using her Colour Brush,she touches her Rainbow Palette with it to activate the brush.She then says,"Indigo is the colour of mists!(Injigo wa, Kasumi no kara~!)She draws two lines while saying "Pretty Cure," then she hits the lines with her brush while saying "Mist Arrow!"(Misuto Aro!)
Kasuko was first seen in episode 6. She is seen drinking a bottle inside a cloth. She then sees Aida, Hinata, Pikako, Hanako and Izumi attacked by some kidnappers when they were playing in the Rainbow Park. She told them to go away. The robbers knows that Kasuko is capable of beating them into a pulp. They go away. Pikako is scared but Kasuko says she only does that to bad people. One of the kidnappers' Colour Heart is fading, and Shira takes it to make a Gun Colourless. The cures transform, but it shoots giant bullets towards the cures. Kasuko mocks them, saying that if they are legendary warriors, they shouldn't be afraid. One of the Rainbow Stones reacted and becomes a Rainbow Palette. Without needing any explanation, Kasuko grabs the Palette and transforms into Cure Mist. She uses her sub-attack, Mystical Wall, to block the bullets. She then uses Indigo Haze to make the Colourless dizzy, then she finishes it off with Mist Arrow..
-Kasuko is the same age as Tsukikage Yuri from Heartcatch!PreCure
-Kasuko always brings the bottle that she is seen drinking from in episode 6. It is currently unkown what is inside or why Kasuko drinks it.
-She is the first and only Rainbow Heart Cure to use all of her sub-attacks at the same episode.