Office worker Yu-mi's life is full of worries. She's about to enter a writing competition and has no ideas, but her romance with a work colleague seems to be reaching a new level. But behind all the outward calmness are they - little human cells that control thoughts, feelings and actions. And the world in Yu-mi's head is in a constant state of stress: Rationality oppresses the Writer, Prudence obstructs Love, Hunger always appears unexpectedly and cannot be negotiated with, and then there is Anxiety, which is simply always at the epicentre of all events.