Chrome

Chrome Dokuro is from the series Katekyo Hitman Reborn!/Reborn!, and is one of the two Vongola Mist Guardians.

History
'''WARNINGS! Mentions of ORGAN LOSS!'''

In Katekyo Hitman Reborn!, Chrome is first introduced during the Vongola Ring Battles Arc, during which Xanxus, the leader of the Vongola-affiliated group Varia, challenges Tsunayoshi, the main character, to become the tenth Vongola leader.

During the Mist Guardian battle, Chrome is the one who comes to fight against Mammon, instead of Mukuro, which leads to most of the main characters believing that she has been possessed by Mukuro, until Mammon breaks her concentration on he r illusions and reveals that most of her organs are made of mist flames when her stomach caves in. Mukuro then makes contact by temporarily using her body and finishes the fight. The Tenth Vongola Guardians ultimately win during the Sky Flame battle.

Not much is revealed about her life before she was in a car accident. She lost several organs and her right eye, and her mother and step-father did not want to donate anything to save her life. Mukuro contacted her via dreams, and was the first person to show that he cared about her, and temporarily replaced her organs with illusions.

Her personality is generally a quieter character who is very loyal to people, and she lives past the ending of the series as one half of the tenth generation Mist Guardians.

Relationships
Mukuro- Mukuro was the first person to show her that they cared, so she's very devoted to him. She has forgiven him for liking pineapples and they once adopted one of Swerve's children.

Kise- They met, had a strange misunderstanding and went on a quest to buy bubble gum together.

Chiruyo Tsukigami- They don't really talk much but they opened a maid cafe together and that's what matters.

Kiyoteru- She was one of the first to figure out how kinky WTTPYLS him is, and tries to warn people not to do yaoi stuff with him occasionally.

Spimon- They first talked because she hates pineapples, but she's recruited him into working at the yaoi boy maid cafe.

Trip- He denies that he's part of a yakuza and she denies that she's part of a mafia. Also, he was hired into the maid cafe.

I could have a few more but this is up to date at the moment.