However, she's too shy and timid to the point she runs away from any sign of kindness given by others, particularly from Kyoko, Haru, and I-Pin, as she never thought that she would ever be accepted by anyone unconditionally.

However, as the story progressed, she became more open to her friends and eventually resolves to become stronger and independent to protect those she holds dear, finally able to stand up for herself with her own power.

Chrome was originally a girl named Nagi (凪) who lived a lonely life with no friends and neglected by her mother and step-father.

When her parents visited her in the hospital, she overheard their conversation which tells that her mother refused to sacrifice her organs to save her and none of them wish for her to live longer than she already has.

Having enough with her sad life, Nagi was ready to die, until she heard Mukuro's voice that told her it won't end.

Realising her potential as illusionist, Mukuro saved her life by creating illusionary organs and invited her to join him, which she agreed.

[3] During the Sky match, she is taken as hostage by Belphegor and Mammon so Yamamoto and Gokudera will give the rest of the Vongola Rings.

[6] While spying on the Millefiore Family, Mukuro engages Byakuran in battle but is severely wounded, causing Chrome's organs to disappear and nearly die.

During her captive, Julie reveals himself to be the first Vongola Mist Guardian, Daemon Spade, who wishes to use her to gain Mukuro's body.

[9] At the last day of Simon Rings' awakening, Daemon undid his mind control of her and remove the illusionary organs to lure Mukuro into possessing her, which he succeeded.

During the final battle, she help Enma by creating a barrier around them with Mukuro's support to protect them from Tsuna's XX Burner to defeat Daemon.

[13] During the third day of Representative Battle of the Rainbow, the cause of her declining health is revealed because she's rejecting Mukuro's illusionary organs as she wants him to see her as an individual, yet at the same time a part of her still wished to live with his illusion.

After finding her resolve, she joins Reborn's team as his representative and helps them defeat two of three Vindices by combining her illusions with Mukuro's.