Description:KokoroYotsuba is a fifth-grader who is clumsy yet also takes good care of herthings. Living alongside her brother, she once understood what her grandmother said to her, regarding that "everything has a soul" and thatthings should be cherished with. One day, a strange egg was born from her colored pencil she cherished the most, revealing to as Luckytama, a Cocotama. However, he is been found by Kokoro after returning from school and for him to exist, he asks Kokoro to sign the "Contract of Secrets", on which she cannot reveal the secret of the Cocotamas to the world and also, must take care of each and everyone of them with great love and care. Now with Luckytama living with his new human friend, Kokoro must make sure she never reveal nor tell their secret while meeting other Cocotamas who either befriends her or cause her trouble.