"Human bonds can be seen. And they can be cut. —However, no one takes responsibility for what happens after the cut."

In this world, there exists a field of study that treats the concept of 'causality' as a branch of medicine.

Causality Medicine—commonly known as "Causality Surgery."

From birth until death, humans are connected by countless threads of causality. There is a cause, and there is an effect. If it rains, you use an umbrella. If you are hit, it hurts. If you love someone, you will eventually lose them.

Everything is causality.

But causality is not always in a normal state. Sometimes an effect arises from a cause that shouldn't exist. Conversely, an effect exists but the cause is nowhere to be found. Causality becomes distorted, tangled, proliferates, and becomes a disease that rots the human body.

That is the 'Causality Cell.' A crystalline body of distorted causality that multiplies within the patient's body. Grudge-cause, Regret-cause, Bond-cause, Death-cause, Fortune-cause—multiple types exist.

As Causality Cells multiply, physical symptoms appear first. Then come memory abnormalities. Eventually, surrounding events themselves are swallowed by the rampage of causality.

And finally—one no longer "acts because there is a reason," but rather "causality dictates the action." Your own will is hijacked by causality.

The one who can cure this is the Causality Surgeon.

However, the Causality Surgeon 'cuts' the patient's causality. Regardless of good or evil, they identify the causality that has become abnormal for the patient and decide what to keep and what to cut.

And—the result of cutting that causality is paid for by the patient, not the doctor.

The Karma Shop. At the end of 3rd Street.

There is a doctor with a rusted sign.

The price list posted on the waiting room wall sees the amounts skyrocket as the items increase.

But the truly expensive thing isn't the treatment fee.

—It's the price of life after the causality is cut.