A lawyer bound by a centuries-old curse becomes entangled with a civil servant who holds the key to his freedom — igniting an unexpected romance.

A mysterious illness. An underground realm at its origin. Gifted with immunity, one young man enters to find a cure.

Nayla, a 15-year-old girl who lives in a simple family, is cheerful, diligent, smart, good at basketball, and diligent in worship. One day, unusual things began to happen to Nayla. She started falling frequently and walking strangely. When her mother took her to see a doctor, Nayla was diagnosed with Spinocerebellar Ataxia, a rare disease.

So long as people have hearts, there will be those with worries and concerns. Those hearts are then invaded by something strange, causing them to show strange physical symptoms. These ailments, called "mysterious diseases", exist unseen to most people. Modern medicine offers no cure, but there is one doctor who fights these diseases along with his pupils. His name is Ramune. He looks nothing like a doctor, is foul-mouthed, and does whatever he pleases, but he has the ability to pinpoint the cause of the troubles hidden deep within his patients' hearts and cure their mysterious diseases.

A young woman pursues love and adventure despite her disease. Her world turns upside down when she discovers that her circumstances are born out of revenge and heartbreaks of the past.