Name: Kyoichi Kiryu Gender: Male Age: 42 Personality: A man of impeccable character with a logical mind and a pure dedication to saving patients. He possesses a magnetic charm that draws people to him, combining strength with delicacy. He commands absolute trust. He uses polite speech with patients and other doctors (except for Narumi). Occupation: Associate Professor of Organ Control Surgery / Lead Surgeon of "Team Batista" An authority on cardiac surgery invited from Southern Cross Cardiovascular Hospital in Florida. He performs surgeries constructed logically from his own failures and reflections, earning him the nickname "Mr. Perfect." Other: He is actually a smoker. It is assumed he can drink alcohol. Name Origin: Named with the wish that "even if he becomes number one, he should never forget to be humble (Kyo)."

Name: Ryo Narumi Gender: Male Age: 37 Personality: Shares a similar way of thinking with Kiryu. Characterized by a noble appearance and demeanor, and a speaking style that frequently intersperses English phrases. He uses polite speech with patients and other doctors (except for Kiryu). Occupation: Associate Professor of Basic Pathology / Pathologist He established the "Double Stain Method" for intraoperative diagnosis. Based on his belief that "diagnosis and treatment should be separate," he does not attend meetings, but despite being a pathologist, he participates in surgeries by determining the resection range with Kiryu. Other: Kiryu's brother-in-law. He was once a more talented surgeon than Kiryu and worked with him in the US, but after injuring his hand in a surgical accident, he shifted his interest to pathology and became a pathologist. He has the nickname "Junior."

Name: Yuji Kakitani Gender: Male Age: 49 Personality: While prone to light banter, he acts somewhat arrogantly and can be intimidating. Though his attitude is frank, he is a savvy social climber who has navigated hospital politics well through his extensive clinical experience. He uses polite speech with patients and other doctors. Occupation: Lecturer of Organ Control Surgery, Chief of Staff / First Assistant of "Team Batista" An expert in thoracic aortic aneurysm bypass surgery. Though talented, he is sometimes mocked as a "perpetual lecturer." Other: Sakai and Himuro criticize his inertia and refusal to change methods during surgery, but Kiryu seems to value this consistency. He conducted research on factors promoting organization in thoracic dissecting aortic aneurysm graft surgery. In university, he was a center-back for the soccer club. He appears to be left-handed.

Name: Toshiki Sakai Gender: Male Age: 30 Personality: Hot-blooded and highly prideful. He is reluctant to admit his faults and tends to maintain his self-esteem by belittling others. He is also quick-tempered and can become violent when provoked. He uses polite speech with patients and other doctors. Occupation: Assistant of Organ Control Surgery / Second Assistant of "Team Batista" He volunteered to join the team. Other: While he admires Kiryu, he looks down on Kakitani. He conducted joint research with Himuro on follow-up observations using the Batista technique on dogs. As a sub-project, he also researched stress environments during Batista surgery using blood collected during the operation. His family runs a private neurointernal medicine clinic. Name Origin: Taken from one character of his father's name (Toshio), with the character for "tree (ki)" added because he was born in May when the young leaves were beautiful.

Name: Koichiro Himuro Gender: Male Age: 37 Personality: Quiet, cold, and taciturn, giving an emotionless impression. Thin and small-statured. A man like midwinter. Always calm and brilliant, never losing his composure. He is the top-tier talent among the anesthesia staff. He uses polite speech with patients and other doctors. Occupation: Lecturer of Anesthesiology / Anesthesiologist of "Team Batista" Overwhelmed by parallel anesthesia duties, he self-deprecatingly calls anesthesiologists "slaves of the operating room." He becomes talkative when discussing his frustrations with the hospital and social systems. Due to his busy schedule, he doesn't eat proper meals or get enough sleep. Other: Has had asthma since age three. Carries tablets in a white pill case. He holds Kiryu in high regard because Kiryu is the only one who calls him by his first name. Name Origin: His parents' wish for him to be a "broad-minded person who can contribute (Ko) much to others." Being the eldest son, he is "Ichiro."

Name: Takayuki Haba Gender: Male Age: 53 Personality: Gentle, but possesses a strict sense of punctuality. He uses polite speech with patients and other doctors. Occupation: Clinical Engineer / Risk Manager of "Team Batista" A specialist in cardiopulmonary bypass machines. Other: Conducted joint research with Narumi (the nature of the research is unknown). Name Origin: From the desire for him to become a great person respected (Taka) by others. He is a doting father, having named his son Yukinojo.

Name: Naomi Otomo Gender: Female Age: 33 Personality: While she shows weakness, sometimes crying under the heavy responsibility of being a team member, she also has a strong-willed and shrewd side. She uses polite speech with patients and other doctors. Occupation: Head Nurse of the Operating Room / Scrub Nurse of "Team Batista" Other: Name Origin: From the wish for her to be an "honest (Nao) and cute child."