Ikuto Tsukiyomi is a teenage boy in high school, contracted by Easter to find the Embryo. He often helps Amu even though he works for Easter. Ikuto actually despises Easter and tries to wrench himself free from them by trying to find the Embryo to grant that wish. He possesses the Dumpty Key which pairs with Amu's Humpty Lock which at first did not fit in the keyhole. Like his father, Ikuto is a skilled violinist. He is the current owner of the Dumpty Key, which originally belonged to Aruto, his father, although Tadase's father had it for a little while. His father is presumed to be dead, but Ikuto refuses to believe it and has set out on finding him. His mother was forced to marry the president of the Easter Company after her husband's violin was found in a foreign country. From her second marriage, she bound her children into working for Easter. Ikuto's personality is aloof, mysterious, and a little naughty. He likes teasing people, especially Amu and Tadase. He is also the older brother of Utau Hoshina. As the series goes on, he grows very strong feelings for Amu — he confessed that he loves her in the same chapter Tadase did, although she believes that he is teasing her. He later surrendered himself to Easter, not wanting to get anyone else involved in the mess he made.