Blue Spinel

Blue Spinel (ブルー スピネル,  Burū Supineru ), more known as Blue (ブルー,  Burū ), is a former Homeworld Gem currently living on Earth, and Ketsume's previous test subject.

Appearance
Blue has light blue skin and black eyes. Her hair is of a darker shade of blue and styled into two buns on the shape of Clubs.

She wears a pair of blue gloves, a white top with navy short sleeves and large shoes of the same color. Her gemstone is takes the form of a blue Club, and located on the middle of her chest. After being released by Ketsume, it was slightly cracked, implying that he damaged it some way.

After reforming, Blue's appearance changes a little. Her buns are now shaped into regular ones, instead of Clubs, her top is now dark blue instead of white, and while still maintaining their overall shape, the tips of her shoes are now facing up in a slightly sharp form.

Personality
In the past, Blue was a very playful and childish Gem who loved to have fun and amuse others more than anything. She was also goofy and enjoyed making "silly" jokes, never taking anything seriously, and smiling all the time. Because she was created just for entertainment, Blue relied in everyone else and was very naive, trusting anyone she met and growing attached to them. Her innocent persona made it easy for her to be manipulated; also because she was too immature, she was often ignorant of the current situations and took a long time to understand things. Another trait she possessed was stubbornness, to the point of annoying people with her insistent pestering, but was not aware of this. She cared a lot about others, especially Beryl, being very loyal. She was also creative and imaginative, liking to fantasize about things. Overall, she behaved and thought just like a young child and had no actual experience on dealing with the world.

Currently, Blue's only objective is to find Beryl, who is considered by her as her "best friend". Because of Beryl's influence, Blue believes that there is nothing wrong with violence if it is being used to prove a point or defend something. She does not recognize her relationship with Beryl as an abusive or toxic one, and will get offended at the slightest insinuation of that. Her disappointment can come off either as childish pouting, like throwing tantrums, or wild rage, like attacking people or destroying things. Her encounter with Ketsume traumatized her and she is prone to bursting into tears over little things, and started to dislike Earth, only staying there for Beryl. She still has some of her previously cheerful demeanor.

Background
Blue used to live on Gem Homeworld. At one point, around 5000 years ago, she met Beryl, who fell in love with her. Unbeknown to Blue, Beryl began plotting for the two of them to escape and live together somewhere. However, when they attempted to put the plan into work, they were captured and banished from Homeworld. They eventually settled down in a floating rock somewhere and even built a house there.

Despite everything, Blue saw Beryl as her "best friend", not as a lover like she wanted (as she didn't understand the concept of romantic love). Instead of trying to understand Blue's feelings and explain her own to her, Beryl simply forced a relationship onto her, and sometimes, even abused her emotionally, using methods such as guilt tripping and gaslighting. Deep inside, Beryl felt guilty for her actions, but never stopped since she didn't know what else to do.

After discovering about Earth, Blue showed interest on going there, but Beryl strictly forbid her from doing so, and overall, ever leaving her watch, insisting that all the two of them needed was each other. Blue never really gave up on that, and from time to time, asked Beryl to go to Earth again, always receiving no as an answer. One day, Beryl realized that what she wanted the most was to make Blue happy, even if they weren't together, and out of guilt, shattered herself, leaving a note telling her she was allowed to go to Earth; she didn't explicitly state her death, however.

After discovering the note, Blue incorrectly assumed that Beryl had gone to Earth and was waiting for her there, and so, went to Earth. There, she met Ketsume and served as his test subject for many years, but after he got all the information he needed about the Gem species through her, he let her go. It is likely that during the years he kept her with him, he slightly cracked her gemstone. Because of the physical and mainly emotional pain she was feeling, Blue retracted into her gemstone, and only reformed recently. She is currently looking for Beryl on Earth.

Beryl
Beryl is considered by Blue to be her "best friend", while Beryl was in love with Blue to the point where it was an obsession. After meeting Blue, Beryl decided to run away from Homeworld with her, only for them to be banished out anyway; for many thousands of years after that, the two lived together without anything else. During this time, their relationship is known to have been rather toxic from Beryl's side, as she kept trying to manipulate Blue to always stay with her and her only. She always declined Blue's requests to visit Earth, which was when she showed her worst side. Eventually, the guilt was too great for her and she realized that she wanted to see Blue happy, even if it wasn't with her, so Beryl shattered herself and left Blue a note saying she was free to go to Earth.

Blue misunterstood this as Beryl saying she had gone to Earth, as she now firmly believed that the two should never be apart, and went to Earth to look for Beryl. After her Gem was cracked, her personality, including her vision of Beryl, became too extreme and she is now very obsessed with Beryl to the point where it took over her life, and she cares about nothing but Beryl.