Siren/Ellen Kurokawa

Siren (セイレーン Seirēn) is one of the four main cures in the series Suite Pretty Cure♪, she is Hummy's childhood friend and singing mentor, both born and raised in Major Land. For years before the series started, 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, traveled to Minor Land to ask to become Mephisto's subordinate. In truth, she was brainwashed to function as a tool so that he could complete the Melody of Sorrow.

She had the ability to shape-shift into any form she wished and often alternated between her true feline form and her alter ego Ellen Kurokawa (黑川 エレン Kurokawa Eren?), using the charm 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 (キュアビート Kyua Bīto?). She uses the light blue Fairy Tone Lary to transform. Her catchphrase is "Can't stop my heart's beat!"

Appearance
As Siren, she is an indigo cat with gold eyes with purple note-shaped markings, silver fur around her neck, and gold rings on her front left paw and tail. On her forehead and back is a hot pink heart, and around her neck is a gold collar with a silver pendant.

As Ellen, her eyes remain the same while her hair is dark purple, reaching the chest with a gold ornament. She wears a white long-sleeved shirt under a black sleeveless jacket, a black miniskirt and stockings with dark magenta markings, a necklace and gold collar, and a pair of boots. After switching sides, she wears a side-tail with a yellow scrunchie. Her lilac top has a dark red heart to match the one on her black vest, a ruffled lavender miniskirt with belt, black stockings, and gold boots. She changes her necklace and gains black bracelets. In the movie, she wears a long-sleeved purplish-grey top beneath a dress whose top is white with black linings and skirt black and two-layered, black socks with grey cuffs and white sneakers.

As Cure Beat, her hair turns lavender and grows in length, being worn in a curled ponytail with a distinctive strand that curls on the right of her bangs. She wears blue heart with feathers, pale blue fabric, and indigo ribbon. Matching her heart earrings and choker. She wears an indigo dress with blouse-style top that has white and dark blue detail, the ruffled neckline is pale blue to match her sleeve cuff. Beneath her Cure Module is a pale and dark blue bow. Her skirt consists of two frilly layers, followed by ruffles in white and pale blue, and an indigo pleat with dark blue lining, a small white ruffled peplum rests over it. On the back is a long, thin pale blue ribbon. Her thigh-length boots are dark blue and indigo with a white bow around the ankle and pale blue ruffled trim. She wears matching colored wrist pieces with a heart design.

As Crescendo Cure Beat, her hair turns lighter and is worn in a tighter curl, the wings of her hair accessory grow while the ribbon and fabric become white. Her dress is mainly pale blue and white with light blue detailing. Her wrist pieces alter in shape and lose the heart design, while her skirt's top two layers grow longer and gain a golden wing cape-like segment to match her wings.

Personality
Before her brainwashing, Siren was shown to be a very kind and caring cat who took care of Hummy and enjoyed her company. But when she began to get envious towards others achievements, she found herself growing cold towards Hummy and she took Mephisto up on his offer. In this time she became cold, calculative, and kept to herself. She lacks sympathy and is unwilling to talk about her pain. However, it was obvious that she was still good deep down, and after Hummy was able to convince her that she was blindly following Mephisto and was letting him manipulate her, she broke free from his control.

After becoming Ellen, she underwent a dramatic personality change. She has become more upbeat and cheerful and regained her kindness. However, she gained the naivety she used to show concern for Hummy having, shown fears that people consider childish or being emotional. She is excited to learn more about the new world she has been brought to, and she shows that she is a passionate and dedicated girl who desires to gain more knowledge and friendships.

Betrayal
Siren, feeling betrayed by Aphrodite because she chose Hummy to sing the Melody of Happiness, goes to Mephisto of Minor Land pledging her loyalty. On the day that Hummy was due to debut as the new singer of the Melody of Happiness, Mephisto attacks stealing the Legendary Score and rewriting the notes to create the Melody of Sadness. He then called forth Siren to sing the new melody. Aphrodite was shocked over her betrayal as she began to sing causing the crowd to start crying and feeling sad. Aphrodite stops the song and spreads the notes to the land where warriors are born. Mephisto sends Siren and the Trio the Minor after them.

First Encounter with Pretty Cures
Siren, in the disguise of Ellen, meets Hibiki first and is eager to take the G Clef sealed in her heart. Hibiki runs outside only to see Kanade holding a record the two girls used to listen to together. Siren sees Kanade has the same G Clef as Hibiki and orders the Trio the Minor to take Kanade's while she takes Hibiki's. Before they even reached the G Clefs, the emblems suddenly shone, throwing back Siren and Trio the Minor. As she regains her footing, she sees one of the notes from the Legendary Score on the record and quickly transforms it into a Negatone which calls forth a monster to attack the city and spread the sorrow. Hibiki and Kanade were angered by this, and the emblems in their hearts came out and transformed into Cure Modules, which allowed the two girls to transform into Pretty Cure.

Betrayed Again
During episode 10, Siren was injured and was about to get hit by a car until Ouji saved her. In his presence, she cannot reveal her true nature to him but seemed to have developed a bond with Ouji. The next day, Siren hesitates due to Ouji's presence and one of her subordinates, Bassdrum, transforms the gifts Hibiki and Kanade received into Negatones which they defeat. Afterward, Bassdrum denounces Siren as their leader. Later, Mephisto declares Bassdrum as the new leader due to Siren's sudden change.

The Big Lie and Being Brainwashed
During episode 13, Siren sees Hummy telling Hibiki and Kanade about the times when they were still friends. Hummy is able to reach her heart and Siren begins to cry. Then, Falsetto and Baritone appear in disguise and inform the girls that there is a "Negatone" wreaking havoc in the town. Once Hummy and the girls are out of the way, Siren sees one of the old contestants who tells her that Hummy told the judges for the audition that Siren had given her a fake score. Mephisto appears and tells her the same thing, but Siren still believes in Hummy. She then tried to oppose him but Mephisto brainwashed her again, making sure he erased her memories of being with Hummy and becoming a tool to serve him.

Rebirth and Regret
After Siren obtains the Fairy Tones and the scattered notes, Mephisto invades Kanon Town and sets up a stage to perform the Melody of Sorrow. Aphrodite speaks with Hibiki and Kanade, asking them to believe in Hummy. However, Hummy is kidnapped by Mephisto and is given headphones to amplify the Melody of Sorrow. As Hummy nonetheless expresses her words of friendship to Siren and sings, Siren remembers the good times she spent with her and is moved to tears. As Mephisto tortures Hummy with the Melody of Sorrow, Siren turns against him and tries to free the Notes, but Mephisto turns them into a Negatone. Hummy manages to free herself and the Fairy Tones, allowing the girls to transform. As Mephisto targets Hummy yet again, Siren calls out and transforms into the Pretty Cure of Miracles: Cure Beat, whilst Hibiki and Kanade defeat the Negatone. Siren, however, is unable to take everything in and runs off.

Everyone becomes curious as to how Siren became a Pretty Cure, especially Siren herself, who finds she can no longer transform into a cat or change her disguise. Left confused as to where to go, she winds up at the church where Mr. Otokichi gives her comfort. Hummy finds her, but she feels she doesn't deserve to be forgiven so easily. As Hummy follows her around, with Hibiki and Kanade also offering their friendship, they are approached by the Minor Trio who create a Tree Negatone. As the Pretty Cure end up in trouble and Hummy is captured, Siren stands to protect and produces a Cure Module, allowing her to transform into the Pretty Cure, Cure Beat. Using her new abilities, she rescues Hummy and defeats the Negatone. After the battle though, Siren is still unable to forgive herself and runs off again.

Forgiveness and Joining the Team
Now known as Ellen, Siren continues to reject Hibiki and Kanade's offer of friendship as she is still unable to forgive herself. She encounters a boy named Mamoru who is hiding from his father. He explains that he ran off with his bag after hearing he was going to work abroad for a year. As Hibiki and Kanade have conflicting ideas to Ellen, they go to search for the father whilst Ellen leaves with Mamoru. Mamoru soon discovers a stuffed animal inside the bag that his father made him and decides he wants to return, helping Ellen realize she's not alone as well. However, just as father and son are reunited, Bassdrum spots a Note inside the doll and creates a Negatone from it. As Bassdrum tries to waver Ellen's feelings, Hummy helps her build up the courage to join in the fight as a Pretty Cure. After defeating the Negatone, Ellen overcomes her worries and officially joins the Pretty Cures.