Aoki Ryuusuke (青木龍介 Aoki Ryūsuke?) is one of the main Cures in Smile PreCure! Royal Prince. He is the son of Aoki Reika aka Cure Beauty, thus having a calm and elegant demeanor. Like his mother, Ryuusuke is very responsible and reliable and is shown to be the school council President of Nanaigaoka First High School. His alter ego is Cure Knight(キュアナイト Kyua Naito?) and his element is ice.