After transferring from Kyushu to a hospital in Tokyo, Reiko begins a new life in the city with her son. Born and raised in Kyushu, she has a gentle and thoughtful personality, always bringing smiles to those around her and selflessly dedicating herself to others—so much so that she often neglects her own needs. To outsiders, Reiko's family appears peaceful, but beneath the surface, turmoil is brewing. A dark presence within the household begins to gradually threaten her life with her son.