The Forever and a Day program is an experiment devised by the gods. Its purpose is to offer a second chance to people who feel stuck in life or are heading towards a tragic end. The program sends them back in time, where they can gain valuable experiences and a fresh perspective on life. However, there are some conditions attached. The participants are only allowed a limited amount of time during each visit, and if they die in the past, they also perish in the present.

Lucy Blanchet is one such individual who feels stuck in life. Luckily for her, the goddess who goes by the name of Hiru has offers her the chance of a lifetime!