The Guardians are the student council of Seiyo Academy to protect the students and the school, and secretly keep the children's heart's eggs safe and preserve them while looking for the Embryo - the legendary heart's egg that has the power to grant wishes, as well as fighting against the Easter Company.
Each of the members has at least one Guardian Character to grant them special powers in tight situations.
The Guardians usually have special or secret meetings in the Royal Garden of Seiyo Academy.
This organization was founded by Seiyo Academy's principal, who is named Tsukasa Amakawa - the first King's Chair, also known as the Founding King.
The Guardians are traditionally recruited with four kids with Guardian Characters in four positions known as the King's Chair, Queen's Chair, Jack's Chair, Ace's Chair.
When a person with three Guardian Characters appears, which is Amu, that person will take the position of Joker's Chair with special missions to attend. Most specifically cleanse those heart's eggs whose owners have tainted with an X.
Guardian Apprentices are later introduced in the anime as most of the Guardians will be graduating at the end of the series, leaving Yaya as the only chair left.
- Hotaru - Rikka's Guardian Character
- Tsukasa Amakawa - The first King's Chair
- Temari - Nagihiko's first Guardian Character
- Rima Mashiro - Former Queen's Chair
- Kusukusu - Rima's Guardian Character
- Kukai Soma - Former Jack's Chair.
- Daichi - Kukai's Guardian Character