Hikari Kujou is considered to be the "life" of the Queen, a part of her spirit that appeared when the Queen as a whole broke up into three parts: the Heartiels, the embodiment of her will; Hikari, who represents the Queen's life; and the Queen Chairect, her heart. She has lost all of her abilities and memories from being Queen and is living as a passive human girl. She makes friends and goes to Verone Academy with Nagisa Misumi and Honoka Yukishiro and works for Akane Fujita's mobile store. Her alter ego is Shiny Luminous.
After the first season, Hikari lost all of her abilities and memories as the Queen and lives life as a passive human girl. She makes friends with Nagisa and Honoka. Typically a very nice, caring, and polite girl, she is also naive due to memory loss. She never gets angry in her regular form, which tends to make some people worry.
Hikari is taken to the Garden of Light in the end, and the Queen reawakens and resembles her transformed form. Later, she grants the rest of the team the final finisher: Extreme Luminaro Max.
She grasps to concept of being Shiny Luminous quite quickly but is always wondering about her past and often stares at the sky.
Hikari has long, blonde hair and yellow eyes. She wears her hair in a side braid. As a civilian, she is seen wearing a pink shirt with a pale yellow shirt with sleeves underneath, jeans, and pink and white shoes. In the Futari wa Pretty Cure Max Heart movie, Hikari was seen wearing a frilly, pale yellow and red dress, with pale pink gloves and pink ballerina-like shoes. In the Futari wa Pretty Cure Max Heart 2: Yukizora no Tomodachi movie, Hikari was seen wearing a pale pink turtle neck sweater and a purple apron with the words 'TAKO Cafe' inscribed on it. Along with it, she wore jeans and pink and white sneakers.
- Heartiel Action - A support move performed by Shiny Luminous, in which she increases the size of her Heartiel Baton and launches it at the enemy, slowing down their movements.
- Extreme Luminario - A combination attack performed by Cure Black, Cure White and Shiny Luminous. Luminous fires rainbow power from her Heartiel Baton which powers of Black and White, allowing them to launch a rainbow coloured blast at the opponent.
- Hikari is the first non-Cure ever to have the ability to transform and have a role equal to Pretty Cure, followed up by Milky Rose. Coincidentally, they are not human during the first season, but became one in the sequel.
- While all other main Cures in the series after Futari wa Pretty Cure Max Heart have pink as their main color, Shiny Luminous is the only one of the three in her series with pink as her main color, which can be considered ironic since she is not even a Cure.
- Even though Shiny Luminous does not fight much in the anime, she will fight in some games if selected, and use the Heart Baton in melee combat.
- Even though her theme color is pink, she more than often wears more yellow.
- Shiny Luminous is one of the youngest characters in the Pretty Cure franchise.
- She is also the first heroine to have her theme color as pink, even though she is not the lead Cure.
- Hikari's birthday falls on 9 September, which is a reference to her family name, Kujou means nine.
- Hikari's birthday is similar to that Hayato Gokudera from Reborn.
- In the Pretty Cure All Stars Suite Flower Card Collection, Hikari is represented by the oxalis, which symbolizes joy and kindness in the Language of Flowers.
- Hikari is very similar to Urara Kasugano:
- Both are blonde.
- Both are the third member of their group.
- Both were very distant when they were first met.
- Both have pigtails once transformed.
- Both have an attack that can immobilise the enemy (Heartiel Uction and Prism Chain).
- Both are the youngest in their groups.
- Hikari is the only Cure who wears her hair in braids.
- Shiny Luminous is very similar to Milky Rose:
- Both hair are in Twin-tails style.
- Both have Special Attacks (Heartiel Unction and Milky Rose Metal Blizzard).
- Both are the special members of the team.
- During the first season of their respective series they both not appear as a human (Queen and Milk).
- Both can transform and have the equal power to Pretty Cures.