This novel combines card elements with a weird atmosphere to quickly establish a world view and a sense of tension, using the classic horror scene of "delivering a message in the rain". The male protagonist is set as a calm and professional exorcist, and the female protagonist is an equally capable partner, using details to show their professionalism and no-nonsense character. Scenes are described, such as an old house in the rain, abnormal letters, and supernatural video tapes, and classic scenes also provide foreshadowing. There are also some novel settings, such as using nostalgic video tapes as a supernatural carrier, the strange task of delivering letters on rainy nights, and the hidden regular death threats, hinting at a greater crisis.
