Hishikawa Rikka

Hishikawa Rikka (菱川 六花) is one of the main Cures in Doki Doki! Pretty Cure. She is one of Mana's childhood friends and the secretary of Oogai First Middle School's student council. Her Cure Ego is Cure Diamond (キュアダイヤモンド).

Appearance
Rikka has navy colored hair that is styled downwards with two side braids joining at the back and going down.Her eyes are dark blue.

Her winter casual costume consists of old styled blue dress, which is where she wears her Cure Lovead, with light blue colored sleeves and dark blue colored ribbon on her neck. She has short royal blue socks and brown shoes. Her summer casual costume consists of a short sleeved white dress with a large dark blue bow in front, blue shoes with white socks. She is also sometimes seen wearing red glasses.

As Cure Diamond, she has blue hair and eyes. Her hairstyle might resemble Cure Aqua's, with curls at the end. Her top is long, like Cure Moonlight's, while the bottom resembles Moonlight's style but at Splash Star's skirt length. The costume overall is aqua, while the sleeves, skirt and inner lining are white. There is a blue ribbon with short ends on her right side, and a blue heart on the left side of her chest. Her sleeves are asymmetrical, with feathers only on the left side. She has simple golden bracelets on her wrists and neck. She wears short white boots with sharp toe tips. On her right side, hangs her Lovely Commune.

Personality
Rikka is a quiet, honest, blunt, not afraid to speak her mind and a very intelligent girl. She is a second year student at Oogai First Middle School, and the student council's secretary. She loves to study, and is a genius at it, being one of the Top 10 scorers in the national trial exams. She is great at observing people and situations. As noted by Mana in episode 9, Rikka is at the top of the class and constantly placed as the first place in her school, however her scores started to drop as she was in second place because of starting to play competitive karuta, as it was seen in episode 14.

Rikka is childhood friends with Mana, since they live near each other. Ever since they were children, Rikka has been taking on the responsibility of looking after the troublemaker Mana, sometimes being taken advantage of. Despite that, she also was always protected by Mana which makes Rikka trust her. She strives to lead a quiet school life, but is often dragged into various things by Mana.

History
Rikka is Mana's best friend and they have known each other since elementary school. She always tries to stop Mana from overdoing things but cannot seem to do so. Her mother works late at a local hospital and her father travels the world as an Archaeologist. Rikka finds out about Pretty Cure when Mana decides to tell her because it is hard for her to keep a secret from her best friend. She later runs into the mysterious merchant who gives her a Cure Lovead that she later decides to use to help her friend as Cure Diamond.

Relationships
Aida Mana: Mana is one of Rikka's very close childhood friends and current schoolmate.

Yotsuba Alice: Alice is another one of Rikka's childhood friends, as they met in elementary school.

Kenzaki Makoto: Makoto is one of her Pretty Cure teammates.

Raquel: Raquel is Rikka's transformation partner who helps her transform into Cure Diamond.

Hishikawa Ryoko: Rikka's mother, she appears as a doctor who is always late.

Hishikawa Yuuzou: Rikka's father, who appears as a professional photographer, and often travels a lot.

Aguri Madoka: She and other Cures met her during the battle with Regina.

Ira: She took him in and looked after him in episode 26 and went against Cure Ace to protect him, Ira has been teased by Marmo of having a crush on Cure Diamond, and he has also called her an 'Angel' in episode 26, whether he does have feelings for Rikka or not is unknown. In the second to final episode he is shown protecting her from a Jikochuu despite him saying after "The one who will defeat the Pretty Cure will be me." In the episode after he is fighting her again before the others can enter Selfish King, he was almost trying to stop her because he said that she could disappear but she told him she had to. At the end of the final episode he is shown looking at her and then smiling before the Selfish Trio leave again. It is believed and wanted by many fans that they have a romantic relationship, as some clues are shown in episode 26. It was confirmed by the producers that Rikka has no romantic interest in Ira.

Cure Diamond
"The light of Wisdom! Cure Diamond!!" 英知の光！キュアダイヤモンド！！ ''Eichi no Hikari! Kyua Daiyamondo!!''

Cure Diamond (キュアダイヤモンド) is Rikka's Pretty Cure alter ego. She represents the light of wisdom.

Transformation
Raquel cries out his name before Rikka first places her transformation Cure Lovead onto Raquel's silver heart medallion object and shouts "Pretty Cure Love Link!" She then spells "L-O-V-E" on her Lovely Commune and the transformation begins. She is seen floating around with her body, except for her head, glowing with blue light. First, her hair glows blue and grows into a long ponytail. Her hair then turns to a lighter blue and her hair accessories and diamond shaped earrings start to appear. Her dress then appears and her Lovely Commune attaches itself to it. Next is her heart brooch, bracelets and boots. Finally her dress ribbon appears on her pelvis and Cure Diamond poses saying her introduction speech.

Attacks
Twinkle Diamond - is Cure Diamond's main attack, with the incantation "Sparkle! Twinkle Diamond!" (煌めきなさい！トゥインクルダイヤモンド！). Cure Diamond activates her attack with the Lovely Commune. It then blinks twice and she points her finger towards the foe, releasing a flurry of blue diamond-shaped energy beams. With this attack, she can also freeze enemies.

Diamond Shower - is Cure Diamond secondary individual attack that appear in Episode 11, firstly, she summon the Love Heart Arrow and set the Diamond Arrow Lovead within, then it shines, she take the arrow and she tap her arrow a couple of times releasing a big wave a diamonds.

Diamond Swirkle - is Cure Diamond's third individual attack performed with Magical Lovely Pad.

Diamond Blizzard - is Cure Diamond's fourth individual attack. It looks like an upgraded version of Diamond Shower and Raquel says the incantation with her. After she uses this attack, she is encased in a diamond-shaped block of ice.

Power-Ups
Like her Cure partners she can Power Up by herself when she takes it seriously in the battle, when this happens a blue light appear around her body.

Etymology
Hishikawa (菱川): Hishi (菱) means "a diamond shape", while kawa (川) means "river".

Rikka (六花): The kanji Rikka (六花) means "snow". Individually, Ri (六) means "six" while ka (花) means "flower".

Songs
Rikka's voice actor, Kotobuki Minako, has participated in several image songs for the character she voices. Many of them include duets with Nabatame Hitomi, who voices Aida Mana, Fuchigami Mai, who voices Yotsuba Alice, and Miyamoto Kanako, who voices Kenzaki Makoto.
 * COCORO♦Diamond
 * Clear Eyes

Duets

 * Natsu no Ryuuseigun (Along with Nabatame Hitomi)
 * Treasure (Along with Nabatame Hitomi and Fuchigami Mai)

Trivia

 * Rikka is the 12th Pretty Cure to be excellent in academics.
 * Rikka is the third Pretty Cure to have "kawa" in her last name. However, she is the only of the three who does not have a color in her family name.
 * Cure Diamond is the first Pretty Cure to wear bracelets instead of arm warmers.
 * Cure Diamond is the fifth Pretty Cure to have a long dress instead of a typical mini skirt.
 * Cure Diamond is the second Cure who uses as ice as her power (Some of her attacks are related to ice). The first one being Cure Beauty from Smile Pretty Cure!.
 * Rikka is the fourth Pretty Cure to have glasses.
 * Cure Diamond is the second Pretty Cure to have a diamond as her symbol. The first is Cure Pine.
 * Rikka has some similarities with Kurumi Erika:
 * Both of their theme color is blue.
 * Both of them became Pretty Cure on the third episode.
 * Both of their fathers are photographers.
 * Both of them use water related powers when they are in Cure form. (Erika uses ocean powers, Rikka uses ice powers.)
 * The two curled side braids in Cure Diamond's hair might represent dog ears, given that her mascot partner resembles a puppy.
 * In episode 42, her zodiac is revealed to be Virgo.
 * Rikka's birthday date, which is September 17th, was revealed by Yamaguchi Ryota himself via Twitter.
 * Hishikawa Rikka/Cure Diamond is ranked as the 1st top anime character for December 2013.
 * Her relationships with Ira are similar to Yukishiro Honoka and Kiriya.
 * Rikka appeared as Cure Diamond to give the 10th anniversary congratulatory message at the beginning of episode 25 of Happiness Charge Pretty Cure!
 * Oddly, her bangs look similar to that of her civilian form instead of her Cure form.
 * Whenever Mana goes out of her way to help someone, she constantly calls Mana "The Happy Prince", after the fable written by Oscar Wilde. She likewise has a tendency to compare herself to the swallow from the same fable.

Gallery
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Previews

 * Cure Diamond official profile (TV Asahi).
 * Cure Diamond old profile (TV Asahi).
 * Cure Diamond full profile (Toei Animation).
 * Official header stance.
 * Cure Diamond profile for Pretty Cure All Stars Everyone Gather ☆ Let's Dance!.
 * Cure Diamond profile in Pretty Cure All Stars New Stage 2: Kokoro no Tomodachi.
 * Cure Diamond's Special Blackboard Profile for New Stage 2
 * Cure Diamond's Full Stance from Pretty Cure All Stars New Stage 2: Kokoro no Tomodachi
 * Rikka official profile (Toei Animation).
 * Rikka official profile (TV Asahi).
 * Rikka with her parents at a carnival in the opening.
 * Rikka wearing her glasses.
 * Rikka without her glasses.
 * Rikka meets Mana for the first time.
 * Rikka smiles.
 * Rikka about to transform.
 * Rikka wearing her Cure Lovead in Episode 3.
 * Rikka with Mana and Alice when they were younger, seen in the DDPC04Episode 4.
 * Rikka smiles in DDPC10Episode 10.
 * Rikka with her mother in DDPC10Episode 10.
 * Rikka as a gang leader in Mana's imagination, seen in DDPC14Episode 14.
 * Young Rikka, seen in DDPC14Episode 14.
 * Cure Diamond's finishing pose.
 * Cure Diamond during her transformation.
 * Cure Diamond in the Doki Doki! Pretty Cure opening.
 * Cure Diamond is forming a diamond suite during her introduction speech.
 * Cure Diamond appears in an ending card in DDPC03Episode 3.
 * Cure Diamond thumbs up to Cure Heart.
 * Cure Diamond during the showing of the episode title.
 * Cure Diamond fights Grey.
 * Rikka appears in Pretty Cure Online.
 * Cure Diamond introduces herself in Pretty Cure Online.
 * Cure Diamond's concept.
 * Cure Diamond's head concept.
 * Rikka's concept art.
 * Rikka's head concept.
 * Rikka's pajamas concept.
 * Cure Diamond official profile (TV Asahi).
 * Cure Diamond old profile (TV Asahi).
 * Cure Diamond full profile (Toei Animation).
 * Official header stance.
 * Cure Diamond profile for Pretty Cure All Stars Everyone Gather ☆ Let's Dance!.
 * Cure Diamond profile in Pretty Cure All Stars New Stage 2: Kokoro no Tomodachi.
 * Cure Diamond's Special Blackboard Profile for New Stage 2
 * Cure Diamond's Full Stance from Pretty Cure All Stars New Stage 2: Kokoro no Tomodachi
 * Rikka official profile (Toei Animation).
 * Rikka with her parents at a carnival in the opening.
 * Rikka wearing her glasses.
 * Rikka without her glasses.
 * Rikka meets Mana for the first time.
 * Rikka smiles.
 * Rikka about to transform.
 * Rikka wearing her Cure Lovead in DDPC03Episode 3.
 * Rikka with Mana and Alice when they were younger, seen in the DDPC04Episode 4.
 * Rikka smiles in DDPC10Episode 10.
 * Rikka with her mother in DDPC10Episode 10.
 * Rikka as a gang leader in Mana's imagination, seen in DDPC14Episode 14.
 * Young Rikka, seen in DDPC14Episode 14.
 * Cure Diamond's finishing pose.
 * Cure Diamond during her transformation.
 * Cure Diamond in the Doki Doki! Pretty Cure opening.
 * Cure Diamond is forming a diamond suite during her introduction speech.
 * Cure Diamond appears in an ending card in DDPC03Episode 3.
 * Cure Diamond thumbs up to Cure Heart.
 * Cure Diamond during the showing of the episode title.
 * Cure Diamond fights Grey.
 * Cure Diamond's concept.
 * Cure Diamond's head concept.
 * Rikka's concept art.
 * Rikka's head cocept.
 * Rikka's pajamas concept.
 * Cure Diamond official profile (TV Asahi).
 * Cure Diamond old profile (TV Asahi).
 * Cure Diamond full profile (Toei Animation).
 * Official header stance.
 * Rikka official profile (Toei Animation).
 * Cure Diamond profile in Pretty Cure All Stars New Stage 2: Kokoro no Tomodachi.
 * Cure Diamond profile for Pretty Cure All Stars Everyone Gather ☆ Let's Dance!.
 * Rikka official profile (TV Asahi).
 * Cure Diamond's Special Blackboard Profile for New Stage 2
 * Rikka with her parents at a carnival in the opening.
 * Rikka wearing her glasses.
 * Rikka without her glasses.
 * Rikka meets Mana for the first time.
 * Rikka smiles.
 * Rikka about to transform.
 * Rikka wearing her Cure Lovead.
 * Rikka with Mana and Alice when they were younger.
 * Rikka smiles.
 * Rikka with her mother.
 * Mana thinking as Rikka was possesed.
 * Yound Rikka
 * Cure Diamond's finishing pose.
 * Cure Diamond during her transformation.
 * Cure Diamond in the Doki Doki! Pretty Cure opening.
 * Cure Diamond is forming a diamond suite during her introduction speech.
 * Cure Diamond appears in an ending card in episode 3.
 * Cure Diamond thumbs up to Cure Heart.
 * Cure Diamond during the showing of the episode title.
 * Cure Diamond's concept.
 * Cure Diamond's head concept.
 * Cure Diamond official profile (TV Asahi).
 * Cure Diamond old profile (TV Asahi).
 * Cure Diamond full profile (Toei Animation).
 * Official header stance.
 * Rikka official profile (Toei Animation).
 * Cure Diamond profile in Pretty Cure All Stars New Stage 2: Kokoro no Tomodachi.
 * Cure Diamond profile for Pretty Cure All Stars Everyone Gather ☆ Let's Dance!.
 * Rikka official profile (TV Asahi).
 * Cure Diamond's Special Blackboard Profile for New Stage 2
 * Rikka with her parents at a carnival in the opening.
 * Rikka wearing her glasses.
 * Rikka without her glasses.
 * Rikka meets Mana for the first time.
 * Rikka smiles.
 * Rikka about to transform.
 * Rikka wearing her Cure Lovead.
 * Rikka with Mana and Alice when they were younger.
 * Rikka smiles.
 * Rikka with her mother.
 * Mana thinking as Rikka was possesed.
 * Yound Rikka
 * Cure Diamond's finishing pose.
 * Cure Diamond during her transformation.
 * Cure Diamond in the Doki Doki! Pretty Cure opening.
 * Cure Diamond is forming a diamond suite during her introduction speech.
 * Cure Diamond appears in an ending card in episode 3.
 * Cure Diamond thumbs up to Cure Heart.
 * Cure Diamond during the showing of the episode title.
 * Cure Diamond fights Grey.}}
 * Cure Diamond fights Grey.}}