A story about astronomy, and saving for the future by traveling back time. 2 Starpiecers tried to save the people who disappeared from the past, but with 1 condition; the Starpiecers must not die from the current timeline, or you may stay dead in that timeline as a Starpiecer. Meet Kanashi Shinsei and Midori Kensei, the duos who signed the contract from a mysterious man. They'll utilize their ability in order to save the people they found, or dug around with more information. Time will travel, from past to future.