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, both are not human during the first season, but became one in the sequel.
- She is the first non-lead Cure to wear a pink dress.
- Even though her dress is pink, her real theme color is yellow. (Notice by the belt's color)
- Hikari's birthday falls on September 9, which is a reference to her family name, Kujou means nine.
- Her zodiac is Virgo.
- Hikari's birthday has the same of Hayato Gokudera's birthday from the Katekyo Hitman Reborn.
- She is the youngest heroine in the team.
- 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.
- Hikari is the first Pretty Cure to wear her hair in a braid, eventually being followed by Rikka Hishikawa.
- Hikari will appear as Shiny Luminous to give the 10th anniversary congratulatory message at the beginning of episode 21 of Happiness Charge Pretty Cure!