In the opening episode, spirited high school student Aina finds her admired older sister Mafuyu, the most popular girl at their school, drawn into the orbit of the mysterious Wolverine Man. What begins as a chance encounter soon leads to subtle changes in Mafuyu’s usual elegance, leaving Aina both concerned and intrigued. Determined to understand the situation, Aina attempts to intervene, only to witness her sister’s unexpected shift toward uninhibited behavior. This encounter introduces new layers to their relationship and hints at further developments in the shared story.