A member of the Guardians. She has three Guardian Eggs and purifies X Eggs born from negative emotions. Tadase was her first love and she likes him, but she also finds herself concerned about Ikuto.

Leader of the Guardians. He likes Amu. He lived with Ikuto and Utau when they were young. He hates Ikuto and is on bad terms with Easter.

- After his violinist father went missing, the mother of Ikuto and Utau (the only daughter of the Easter family) remarried. - His stepfather is the Director of Easter. The Director forces and threatens Ikuto to create X Eggs and find the 'Embryo,' which is said to grant wishes. - He follows the Director's orders to protect Utau and his mother. - A habitual truant at school. - He always carries his father's favorite violin and plays it occasionally. He has an enigmatic personality, but his clumsy and blunt nature often leads to misunderstandings. - He feels deep guilt for the many misdeeds he was forced or coerced into doing as a puppet of Easter. - He is uncomfortable around dogs. His favorite phrase is 'just enough.' - He relies on Guest.

- Ikuto's younger sister, three years his junior. - Like Ikuto, she works for Easter to atone for their father's actions. She extracts X Eggs by performing Character Changes with Iru while singing. - While she cooperates by providing X Eggs to Easter, she personally seeks the Embryo with the goal of 'saving Ikuto.' - As a child, she loved singing and was a pure, kind girl who wanted to make people happy with her voice. Growing up under Easter's control like her brother, she lost her innocence and became a corrupted puppet of the company.

Ikuto's Guardian Character. A cat-like, mischievous spirit who loves and follows Ikuto everywhere.

- Ikuto and Utau's stepfather. - The Director of Easter Company. The root of all evil in this story and the primary villain. - He married Ikuto and Utau's mother to take over Easter and find the Embryo.