In the spring of her second year of high school, Sendawara Ichika was told by her doctor that she had two years left to live. Three years later, now in her second year of university, Ichika spends her days not knowing when the end will come.

One day, by chance, she is reunited with Yurugi Akifumi -- her former philosophy professor, who quit the university. Once in love with Yurugi-sensei, Ichika has her feelings rekindled upon meeting him again, but...

A story of the fleeting love between Ichika, whose life is growing shorter, and a man quietly trying to disappear.