Be With You (KAWASHIMA Sai)

Takumi's wife dies at the age of 25, leaving behind their son, Yuji, and a very special picture book. It tells the story of those who die–remembered by the loved ones left behind–going to a planet called Archive, and return to visit when the rainy season comes. Suddenly, the picture book seems to come true, when Mio shows up… without a memory.