Sena Shirai, a teenage shut-in, thoughtlessly wishes for her school to explode or the world to be destroyed so she will not have to venture outside. On her 18th birthday, she decides to leave the safety of her home on a whim, only to die in a traffic accident shortly thereafter.

When Sena is reborn into a fantasy world where magic users make up half the population, she discovers that her unique abilities are "Explode" and "Destroy." Believing that she is a danger to others, she spends most of her second childhood living in isolation with her mother in Ludfalla Forest.

Even after her mother passes away, Sena remains in the forest and becomes known as a witch amongst the townspeople. On the day she turns 18 again, she has a chance encounter with a handsome stranger who collapses and requires care until he regains consciousness. The young man, Keith, encourages Sena to break through her physical and emotional boundaries, culminating in a suggestion that they journey together. Will Sena take charge of her future this time around, or is she fated to relive her forlorn past?