Ruby Hoshino

Main article: Ruby Hoshino/Gallery
Ruby is a beautiful young girl of average height with blonde hair that she ties in a side ponytail (much like how her late mother Ai Hoshino does) and possesses pink-ruby colored eyes with a six-star on her left eye like her late mother.

Ruby has been stated to resemble Ai by many people, such as Aqua Hoshino and Kana Arima where Kana herself confirmed that her keen nose in industry "can sense potential in this girl" and it reminds her of Ai. The resemblance grows stronger when she wears a purple wig, to the point that it shocks others especially Akane Kurokawa.

In her past life, Ruby was a frail girl who died of anaplastic astrocytoma and could barely walk a few steps without stumbling. Now overwhelmed with joy as Ruby Hoshino, the daughter of her favorite idol, Ai Hoshino, takes her life to the fullest, Ruby has given herself the goal of becoming an idol singer, not only to follow in her mother's footsteps, but also to fulfill her promise to Gorou Amamiya.

Unlike Aqua who is calm, calculated and discreet, Ruby is the polar opposite of him as she is extroverted, outgoing, loud, optimistic and communicative compared to her brooding brother. She is most apparent in the connections she makes with others. At the same time, Aqua only does this to further his agenda. She doesn't share her brother's opinion of hunting down the culprit who killed their mother, instead moving on from that incident and focusing on her dreams. She persists in this notion to the point where she often conflicts with her brother's interests.

Ruby tends to speak her mind without a filter, often referring to Kana Arima as the "gourd girl" and the "girl who will lick a lying snitch," much to Kana's displeasure. Additionally, Ruby has utilized the "airhead sister" persona to her advantage in the media as a character she created to promote herself.

She is the biggest defender of her mother Ai's secrecy and reputation.

Ruby's greatest asset has repeatedly been noted to be her natural immense beauty. Kana Arima also claimed that she has a charisma about her that draws people in. In addition, her mother taught her how to dance from an early age and even Aqua Hoshino noted that she indeed possessed a natural talent. However, Ruby lacked in arguably the most vital area for being an idol: singing; only scoring a mediocre 38 at karaoke. She also held herself back by refusing to resort to any underhanded tactics, causing Minami Kotobuki to believe that Ruby was too "pure" for the cutthroat entertainment industry.

The name Ruby means "lapis lazuli" (瑠) (ru), "beautiful" (美) (mi/bi) and "clothing, garment" (衣) (i).
Just like Aquamarine, Ruby is a gemstone that is known for it's red coloring.
Just like her older twin brother Aqua Hoshino, Ruby's name is a reference to her eye color.
Ruby's surname Hoshino means "star" (星) (hoshi) and "field, wilderness" (野) (no).

Ruby's mother, Ai Hoshino, has one star in each eye; Ruby inherited a star in her left eye and her brother Aqua Hoshino inherited it in his right eye.
Her star later becomes blackened and she gains an additional black star in her right eye after using dirty tactics to rise in the entertainment industry.
Ruby wants to be an idol like Ai once was.
Ruby once pretended to be Amaterasu, the goddess of the sun in Japanese mythology. While the scene is played as a joke at the time, it is later revealed that she and Aqua died (in their past lives) and reborn in the town of Takachiho in Miyazaki prefecture. And as Akane Kurokawa explained during that chapter, a cave near Takachiho is where Amaterasu once shut herself in.
If Ruby is interpreted to be based on Amaterasu, then Aqua would be based on one of Amaterasu's siblings, likely to be based on Susanoo.
Ruby's height is 158 cm, making her the tallest B-Komachi member (compared to Kana Arima's 150 cm and Mem-Cho's 155 cm).
Ruby applied to be an idol at 14, but she was rejected and had to wait two years before applying again.
Ruby is in Class 1-F during her first year and in Class 2-F during her second year at Youtou High School.
Ruby starts high school at 16
Ruby's glowstick idol color is red, which is the same color as Ai.
Kaguya Shinomiya from Kaguya-sama: Love is War has interacted with Ruby, taking photos of the latter as a part of a job.

17

1.58 cm.

Idol
Youtuber
TV Personality

Ai Hoshino
(Biological mother)

Ichigo Saitou
(Adoptive father)

Miyako Saitou
(Adoptive mother)

Aqua Hoshino
(Older twin-brother)

Kana Arima
(Friend, Partner)

Mem-Cho
(Friend, Partner)

Shun Yoshizumi
(Former manager)

Minami Kotobuki
(Friend)

Frill Shiranui
(Friend)

AGE
18

HEIGHT
172 cm

Appearance
Main article: Aqua Hoshino/Gallery
As a child, Aqua was often called cute by those around him. As he grows older, Aqua becomes a relatively tall boy who is described as "handsome" with blonde hair, much like his younger twin sister Ruby Hoshino. He also long bangs hanging on the left side of his face and aquamarine blue eyes, which his late mother Ai Hoshino named him after, that features a star in his right eye, symbolizing that he and his sister are halves of their mother. Due to being Ai's son, many people were able to point out their similarities despite being unaware of his pedigree. Much to Aqua's dismay, as before Chapter 105, he wanted to keep the truth about his late mother from being known to the general public.
Personality
Before the tragedy that struck his family, Aqua was considered relatively normal other than his unparalleled prodigious talent in acting even as a child and his quick wit and intelligence like reading complex books. With him retaining his past experiences, he accomplished many things not expected for someone his age. Performing acting jobs was something he was open to and excelled at.
After the tragedy that killed his mother, Ai Hoshino, he changed and became cold, calculated, cunning, and discreet, willing to do whatever means necessary to see his goal of finding his father through. His psychological trauma from Ai's murder tends to resurface anytime he seems to forget his goals.