After an illicit affair at work falls through, office worker Ushiro Akechi is wallowing in quiet desperation and stumbling toward ending it all. What she really needs is an older sister to talk her back from the edge... Luckily, she's about to meet one— from the other side! Self-proclaimed Guardian Spiritual Older Sister Masako is ready and waiting to take Ushiro under her wing! Together can they turn a brush with death into the start of a gloriously funny new partnership!?