The episode begins with Keitaro meeting a new student, Ai Kamiyo, a lively and fashion-conscious first-year high school student. At first, Keitaro is overwhelmed by her energetic personality but comes up with a game involving mini donuts to make their study session more engaging. As they spend time together, Ai reveals that she has experienced paranormal activities, including sleep paralysis and the sensation of something grabbing her ankle. She believes that the spirit of her deceased older brother protects her from evil spirits but also prevents him from resting in peace.

Keitaro introduces Ai to Yayoi Hozuki, his first student and a talented exorcist. Yayoi performs a ritual to capture the spirit haunting Ai and believes she has succeeded. Later, however, Ai reveals that she is destined to be abducted by a god who has fallen in love with her when she turns twenty—a fate that runs in her family. This revelation leads Yayoi and Keitaro to realize that the spirit they captured is actually a god and that Ai is engaged to a divine being.

As the episode progresses, it becomes clear that the energy emanating from the god engaged to Ai attracts evil spirits. Yayoi, Keitaro, and Ai, along with Yayoi’s cousin and Keitaro’s girlfriend Eiko, decide to leave Ai’s apartment due to the increasing spiritual activity. Yayoi plans to retrieve an item to purify the apartment, and Eiko offers to drive her home while inviting Ai for a sleepover.

The episode ends on a cliffhanger: Keitaro senses the presence of an evil entity approaching as they prepare to leave the apartment.