Aiba Tsubasa has astounding mathematical powers. He has two younger brothers: Riku, a naive but kind-hearted university student, and Umi, who was born with a weak heart and has no way to be saved except through an organ transplant. In order to help Umi, their mother Takako, a gifted surgeon, had left Tsubasa and Riku who were still very young and sought refuge with a medical research facility.
The facility is a
