Siren (Ellen Kurokawa)

"Can't stop my heart's beat!"

- Siren

Siren is Hummy's childhood friend and singing mentor, both born and raised in Major land. For years before series start, she was Major Land's Fairy of Songs, and sung the Melody of Happiness every year. However, for the current year, Hummy was chosen to sing it instead. She, allegedly feeling betrayed, defected to Minor Land to ask to become Mephisto's subordinate. But in truth, she was brainwashed as a tool so that he could complete the Melody of Sadness.

She had the ability to shape-shift into any form she wishes, and often alternated between her true feline form and her alter ego Ellen Kurokawa, using the pendant on her necklace. She could also summon Negatones from the scattered musical notes using the pendant. However, after becoming Pretty Cure, she has lost her pendant and thus both of these abilities.

Ellen's alter ego is Cure Beat. She uses the light blue Fairy Tone Lary to transform.

Appearance
As a cat, Siren has smooth, dark purple fur with lighter purple fur around her neck. She has a pink heart-like marking on her forehead and her back and she has several golden bands tied around her. Like Hummy, she has similar music note markings around her eyes.

As Ellen, she has mid-length dark purple hair, acessorized with a twisted golden band tied around one strand. She has sharp yellow eyes and an angular face. She wears a basic white shirt with a sleeveless, black jacket, a yellow choker, dark gray bracelets on each wrist, a short black skirt, long stockings and small boots.

When she became Cure Beat, Ellen replaced her twisted golden band with a yellow scrunchie, which ties her hair in a side ponytail on the left side while letting the rest of it down. She also now wears a long-sleeved light purple shirt with a pattern of pink hearts on the front over a long-sleeved white shirt, a short black waistcoat with a pattern of pink hearts on the left, a short pink heart-shaped pendant, black bracelets on each wrist, a lavender ruffled skirt with a black belt, black stockings and short sand-colored boots.

As Cure Beat, her hair becomes wilder and longer, and is tied to the side with a feathered bow. Her costume is slightly more elaborate than the previous two precures, featuring many more frills. Her boots are knee-length and her gloves are wrist-length and fingerless.

Personality
Before being brainwashed Siren was a kind cat. She always cared for Hummy despite her being naive to most things. However she could get very envious of other people's achievements, such as when Aphrodite chose Hummy over her to sing the Melody of Happiness. After being hired by Mephisto she was cold, calculating, un-sympathetic and unwilling to open up to people. But there was still good in her, when Hummy managed to convince her that she was blindly following Mephisto and was being used. Her earphones broke and became Cure Beat.

As Ellen, she underwent a dramatic personality change. She has become more upbeat and cheerful. She was also shown to be much kinder, but with this new-found kindness also came a streak of naivety, such as being easily offended or being prone to childish fears. After a chat with Hibiki and Kanade she became excited at the prospect of starting school. So much so, she spent the whole night practising her introductory speech, showing just how passionate and committed she was to being accepted as a friend.

Trivia

 * Siren is the first mascot-like character to be a villain. She is also the second mascot-like character to become a Pretty Cure, the other being Milk, who obtained status equal to that of a Pretty Cure.
 * She is the first Mascot to be given the title 'Cure'.
 * Siren is among one of the many the villains of the franchise to eventually join the side of the protagonists, the others being Kiriya, The Kiryuu Sisters, Bunbee and Setsuna Higashi.
 * Siren is the second villain to become a Cure, the other being Setsuna.
 * Siren also has a human form like the mascots from Yes! Pretty Cure 5, Yes! Pretty Cure 5 GoGo!, and Coupe from Heartcatch Pretty Cure. She first introduces herself in this form to Hibiki as Ellen.
 * Although her main form is Ellen, Siren also seems to be able to disguise herself as any human, she is seen doing this to try to fool the Cures.
 * Siren is the only mascot character besides Hummy to be a cat.
 * Siren as Ellen once used her abilities to decrease Hibiki and Kanade's Harmony *Power by disguising herself as a transfer student named Sakura Houjou.
 * The necklace Siren used to transform into different forms broke when she first became Cure Beat, resulting in her being "stuck" as a human.
 * It is revealed in episode 24 that Siren/Ellen is afraid of crabs, which Hibiki and Kanade refer to as cute.
 * Siren/Ellen is similar to Miki with both sharing a blue theme colour and a fear of underwater animals. (Miki's being octopuses and Siren/Ellen's being crabs.)
 * While Hibiki, Kanade and Ako refer to Siren by her human form's name, Ellen, Hummy, Trio de Minor and most other Major Landers refer to her as Siren, her true name.
 * The power behind Siren's form changing necklace is unknown.
 * Siren/Ellen is the lightest among the three (Hibiki, Kanade and Siren/Ellen).
 * Siren/Ellen cat form is similar to Cure Muse's Cure form.
 * Siren/Ellen/Cure Beat starred in Pretty Cure All Stars DX: 3D Theatre.