In this clip we see a family sitting around in their house doing work into the night. This shows the extent to which some Japanese families, even the children, have to work to make ends meet. We can also see common elements of a Japanese household. In the rear of some of the shots we can see a room with tatami mats, zabuton, and futon. The father is wearing something common to many blue-collar workers in Japan. You can see everyone from carpenters, to constructions workers, to vendors running food stands wearing these head wraps and similar clothes.
The entire clip is a wonderful example of casual or plain speech. A student of Japanese should note the forms used and ways of addressing each other in a Japanese household. The type of banter going back and forth between the family members is different than the Japanese taught in the classroom, but can be just as, if not more, important than polite Japanese when spending time in Japan.
The topic that the family is discussing tells us about Japanese society. We can see that adultery and lineage are very important and that adults may berate children if they do not fit into social norms. The boy is crying because men are telling him that his dad is not his father and that all of his siblings have different fathers. The fact that this is in the film shows that this is not out of the realm of possibilities in Japan, even if it is not a common occurrence. The emotions behind such attacks would not be out of the question in Japan. The father very artfully comforts his son and tells him to confront his bullies and shame them into leaving him alone. This clip is a great glimpse into a Japanese household dealing with real problems.