Shigofumi unfolds in a world where the dead can send one final message to the living. These letters, known as shigofumi, are born from powerful feelings left unresolved at the moment of death—love, longing, resentment, hope, or regret—and they reach people who may be waiting for answers or trying to avoid them entirely. The quiet and mysterious Fumika Mikawa serves as one of the couriers charged with delivering those messages, traveling with her talking staff and partner Kanaka to make sure every shigofumi reaches its intended recipient, even when its contents reopen grief, guilt, or buried conflict.
As Fumika moves between the worlds of the dead and the living, each delivery exposes private wounds, family rifts, and the tragedies that bind the sender and receiver together. The letters reveal the deepest secrets of both the recently deceased and the people they leave behind. Yet the series also keeps its focus on Fumika herself. Shigofumi mail carriers are dead humans who normally retain the appearance they had just before death, but something about Fumika does not fit that rule, and the mystery surrounding her past gradually becomes central to the story. Who she was before becoming a carrier—and why she seems different from the others—haunts the series as much as the messages she delivers.