Eren Kunashiri is a 16-year-old female student in Class 2-A at Suginami Second High School. She stands 158.6 cm tall, weighs 50.5 kg, has blood type A, and possesses distinctive pink hair.

Initially appearing lonely and timid, she simultaneously projects a contrasting facade of bravado and outward courage. Accumulated experiences drive her personal evolution, leading to greater internal fortitude and the demonstration of direct courage when confronting difficult situations.

Following the deaths of multiple male participants, she opens an envelope of rights originally belonging to Saneatsu Narita. This act grants her the special ability known as the "Obedience Right." During a critical operation targeting the overthrow of the game's mastermind, the Emperor, she partners with participant Kazuhiko Satou. Together, they undertake a mission to shut down a power plant. Her development centers on her transition within the context of the life-threatening challenges faced.