After losing his arm in a car accident, Yeong-gi Han, a talented high school goalkeeper, undergoes a medical transplant as part of a clinical trial with SC Bio. However, when a virus known as "mechanism" breaks out worldwide, strange entities pursue his soul. In a moment of desperation, a mysterious woman rescues him and reveals the secrets behind these events that will stay with him forever. Check out the original webtoon and official translations for more details.