During a mission with Megumi Fushiguro and Satoru Gojo, a Jujutsu High student is ambushed by Mahito, who destroys the protective necklace she has worn since birth—an object sealing a dangerous curse within her. At first, nothing seems to happen. Then the seal breaks. An ancient, unreadable curse begins to manifest across her throat like living script, signaling the awakening of something far older and more unstable than anyone anticipated, leaving even Gojo momentarily uncertain of what is about to happen next.