I am now convinced Google thinks I want to join the yakuza. Sigh. Why did I not remember to do incognito searches? None-the-less, the initiation was fascinating to read about. Though, some sources listed 1 cup and others listed 2, and the new member keeps the cup with them as a reminder. I chose the first because I felt it better represented the pyramid structure of the organization. Those at the top always get more.
Keep in mind, present-day the mob in Japan has a really tough time because the government is cracking down. So the feeling you get from this article is an older one, closer to the mob heydays.
Until I get my research notes posted on the Yakuza article, I'll post some of it here in case it's of interest.