I Got the Power of Invisibility, So I Decided to Enjoy Everything

One day, the protagonist overhears their mother and younger sister in conversation and realizes the sister has long harbored deep resentment toward them. After a heated exchange, the protagonist retreats to their room, frustrated and angry. A mysterious call arrives from an unknown number—a call the protagonist instinctively tries to reject, but it connects anyway. The caller speaks in an unsettling tone before the protagonist hangs up in frustration, catching only fragments of the final words. Hours later, the protagonist discovers something impossible: their sister no longer reacts to their presence. She acts as though they are invisible. As the protagonist grapples with this inexplicable phenomenon, they begin to suspect the mysterious phone call was real—and that something far stranger is at work.