Happy Child first shows himself to the Mew Mews when he retrieves Royal Highness. He makes his main appearance during the second attack on Mew Berry. Happy Child is able to teleport himself, float in mid-air, speak directly into other people's minds, and attack with ultra-sonic waves. In the flashback where the Crusaders first met Duke, Happy Child attempts to commit suicide by jumping off the roof. The others call out to him, using the name "Utamaro", but they are not able to stop him. Duke saves him by catching him when he goes over the roof's edge.