This synopsis will contain spoilers!
Bird is a 27 year old man who is about to be a father and dreams of going to Africa. The book begins with Bird purchasing a map of Africa while his wife is in labor. He is killing time between calling his mother-in-law to check up on the process of the delivery. After getting into a fight with a group of thugs in an arcade, he heads home where he soon hears from the hospital. His wife is fine, but the baby is "abnormal". He races to the hospital where he learns that the baby has a brain hernia. Though there is practically no chance the baby will develop normally, he is taken to another hospital that specializes in brain surgery.
Bird leaves the hospital, thinking the baby will soon die. Bird goes to see his father in law and let him know what happened. He is given a bottle of whisky. Bird goes to see his girlfriend Himiko, knowing she won't mind if he drinks so early in the day. He finishes the bottle of whisky and passes out. Hungover at work the next day (he lectures at a cram-school), he throws up while teaching. He leaves school, but not before a student accuses him of being hungover.
At the hospital, Bird intimates to a doctor he does not want a baby that will not develop normally (a sentiment his mother-in-law also implied before Bird left for the new hospital). The doctor subtly tells Bird that he can give it sugar water instead of milk to ensure the baby does not get stronger, thus preventing him from getting the surgery necessary to fix the hernia. Bird returns to Himiko's and asks if they can sleep together. They engage in various lewd sexual acts.
Bird is fired at work the next day (though technically he will finish out the current semester). Meanwhile at Himiko's he waits anxiously for a call from the hospital to learn of the baby's death. Himiko and Bird continue to sleep together but the call does not come for some time. Eventually they call him in, but it is to schedule the surgery. Bird says he would not like the operation to happen, and he takes the baby.
With Himiko's help, he takes the baby to an abortionist. He and Himiko plan to sell her house and travel to Africa. Not long after leaving the baby at the clinic, HImiko and Bird are at a bar. There, Bird finally realizes can cannot continue to run from the baby. He returns for the baby. Some time passes and it is a week after the operation. The baby did not have a brain hernia, but just a benign tumor. He could develop normally, but there is still some chance he will have a low IQ. Bird's wife, mother-in-law and father-in-law all commend him for the actions he took to save the baby.
Himiko leaves on a boat to Africa with another of her lovers. Bird's father-in-law tells him his nickname no longer suits him. Bird decides to look up the word for forbearance in the Slavic dictionary he received from a friend.
I don't remember ever being as disgusted with the main character in a book as I was with Bird. How could he, upon seeing his new son, not want …- April 4, 2010
Kenzaburo Oe the Last Line of in A Personal Matter