This time, as the fourth installment in the series, it targets women working at "buses," "bookstores," "lingerie shops," and "soba shops." When a woman suddenly experiences a perverted act and realizes it's from a same-sex individual, she is bewildered yet resists. However, a persistent high school girl uses a love potion to engage in perversion again! Gradually, her breathing becomes erratic, and her body heats up... With persistent teasing and passionate kisses, the older sister is made to feel it, forgetting her work as she becomes addicted to the pleasure of lesbianism!!