Matoi Sumeragi desires a simple life away from the spotlight. She attends school and works part-time at Yuma Kusanagi's family shrine, finding comfort in her routine. However, her peaceful existence is disrupted when a malevolent entity known as a Night invades the shrine. With the help of a god, Matoi banishes the Night. As Matoi and Yuma grapple with the aftermath of the attack, they encounter Claris Tonitolus, a seasoned exorcist from the Vatican, and Haruka Luciela, an agent of the covert Night defense group IATO. Though the identity of the culprit remains unknown, Matoi must harness her newfound abilities to safeguard her loved ones and retain her formerly ordinary life.