"15 Bishōjo Hyōryūki OVA" is a two-episode anime OVA that adapts a survival-themed narrative centered around a group of high school girls stranded on a deserted island. The story begins when a group of 15 female students and their teacher embark on a school trip aboard a cruise ship. During the voyage, the ship encounters a sudden and catastrophic storm, leading to a shipwreck. The girls and their teacher are washed ashore on a remote, uninhabited island, where they must rely on their wits and teamwork to survive.

The narrative focuses on the dynamics of the group as they face the challenges of their new environment. The girls come from diverse backgrounds and possess varying personalities, which leads to both cooperation and conflict as they struggle to adapt. The teacher, who serves as a maternal figure, attempts to guide and protect the students, but her efforts are often complicated by the girls' differing opinions and emotional responses to their dire situation.

Survival becomes the central theme as the group works to secure basic necessities such as food, water, and shelter. They explore the island, discovering its resources and potential dangers, including wild animals and harsh weather conditions. The story highlights their ingenuity and resilience as they devise ways to overcome these obstacles, such as building makeshift tools and creating a system for rationing supplies.

Interpersonal relationships play a significant role in the narrative. The girls' bonds are tested as they confront fear, frustration, and the uncertainty of their future. Some characters emerge as natural leaders, while others struggle with feelings of helplessness or isolation. The group's unity is periodically threatened by disagreements and personal conflicts, but they ultimately learn to rely on one another to endure their ordeal.

The OVA does not delve deeply into long-term survival or rescue efforts, instead focusing on the immediate challenges and emotional struggles of the characters. The story concludes with an open-ended resolution, leaving the fate of the group ambiguous and emphasizing the ongoing nature of their survival journey. The series provides a straightforward exploration of human resilience and the complexities of group dynamics in extreme circumstances.