Ryō is a visitor to the island where her mother once lived. She travels there after her mother's sudden demise, Ryo feels that the answer to her mother's odd behaviour is within her mother's origins. Despite how her mother had bade her never to return to that island and to never associate herself with Hotaruko, Ryo nonetheless feels that something should be done in order to explain her mother's eccentric sexual behavior and what caused her to act so oddly.