A young man suffers from split personalities, caused by a carbuncle.A young man suffers from split personalities, caused by a carbuncle.A young man suffers from split personalities, caused by a carbuncle.
Apart from the carbuncle, Koichiro is also suffering from multiple personality disorder, or schizophrenia, with at least 2 other personalities mentioned (one was a female named Ryuko, and another man named Jun).
Black Jack: Even though I was too late to save this case, I learned a valuable lesson: no matter how well one wields a person's scalpel, it can't cut away a person's soul. And if such a scalpel existed, I would be the first in line to place several orders for them.