Several years after the death of his wife, Itsuki is raising his child alone while working at Heaven's Messenger, a company that helps bereaved people to connect with their deceased loved ones. Meanwhile, picture book author Makoto Mikuriya is struggling in her marriage to the heir of the Mikuriya Group, as well as with her controlling mother-in-law.
One day, Itsuki receives a request from Koharu Ayukawa, who has only three months left to live. She wants to show her daughter how she intends to spend her final days and asks Itsuki to help her organise her belongings before she dies. That daughter turns out to be Makoto.
Itsuki and Makoto are drawn to each other, but Makoto’s social status complicates their relationship. Matters worsen when the Mikuriya Group becomes embroiled in a lawsuit implicating Heaven's Messenger, forcing Itsuki and Makoto apart.