A free spirit owner with the charm of disarming people and a detective who pursues the truth of ‘S-line’. Caring for his father and nephew 'Sun-Ah' who suffers from dementia.

A high school ethics teacher who seems kind to everyone because of her youthful appearance and empathy, but has a strange charm.

A high school student born with the ability to see the ‘S-lines’ from birth like fate. Considered herself a cursed child and chose the life of a reclusive hikikomori.