You might know the population of Japan. But I cant exactly feel the amount of human Japan are populated with until now. A brief google check will tell you 127,433,494, and 10% of them are 'densed' in Tokyo. Compare to Malaysia 24,821,286.. I think we have a lot of 'work' to buck up in beating the number.
A Saturday trip to Roppongi (六本木）, Harajuku （原宿）& Akihabara（秋葉原) will definately give you an idea how packed Tokyo is.
Or wearing full suit coat, school uniform & Kimono to a wedding.
Human, marvelous creatures!