In the thrilling sequel to "Volcano," "Respirator" catapults Arella and Jisung into a maelstrom of cosmic chaos. Their serene life at JYP Entertainment is shattered by the arrival of the "Eternal Echo," a mysterious force that distorts time and reality, unleashing unsettling visions of alternate futures and buried secrets. After Arella's self-sacrifice and her return to her human identity as Ae-ri, Jisung is tormented by haunting memories of their past life. As the Eternal Echo's disturbances escalate, Jisung is desperate to shield Ae-ri, who is starting to experience eerie sensations and fragmented memories from her celestial past. Facing a world that is rapidly unraveling, Jisung and Ae-ri must navigate treacherous realities and confront formidable cosmic forces. In "Respirator," their love is put to its ultimate test. Can they uncover the truth behind the anomaly and restore balance before their destinies are irreversibly altered?