The episode begins with Teru and Iko Koishikawa, the girl Teru couldn't save during a previous incident. They talk, and Iko mentions that she transferred schools due to her leg injury. Teru worries about what Iko thinks of her alter ego, Shy.

Later, Iko experiences pain in her leg, and Teru takes her to the nurse's office. There, Iko notices that Teru resembles Shy, the hero who saved her. She holds no grudge against Shy and explains to her that heroes work hard for others. This emotional moment is interrupted when a mysterious boy appears in the nurse's office. He claims to have "freed" Iko's heart, which had been "locked away."

Suddenly, Iko's emotions spiral out of control, and her heart materializes as a black crystal. Teru's support AI, Shrimpy-san, identifies the crystal as the source of Iko's emotional turmoil. The mysterious boy reveals that he wants to free hearts from their "tiny cages."

Teru recalls her grandfather's advice about the importance of living for others and how it brings happiness. She decides to confront the emotional chaos by placing the crystal near her own heart. The crystal shatters, and Iko regains her composure. Teru advises Iko to pass on kindness to others if she ever feels guilty.

The episode ends with an emergency alert confirming that the mysterious boy has been spotted in Japan. Teru and Iko share an intimate moment as Iko thanks Teru for saving her.