The most common definition and symbol of the number nine patience, meditation, harmony, it represents the inspiration and the perfection of the ideas. It is the expression of "the power of the Holy Spirit", according to Etchegoyen. Symbolize the plenitude of talents, the reward of the tests. Symbol of the creation and the life as a rhythm and development. As a product of 3 x 3, it is the expression of the perfection, the symbol of the virile power, in addition to be associated to the couple. Nine is the number of the one who accomplishes the divine will. According to the Cabal, it is also the number of the achievement. The freemasons have made it the eternal number of human immortality. Being the last simple number, it is the number of finalization or finition. It is therefore the most complex, that marks the full lighting up of the numerical series.  This number was considered as sacred in Egypt and in Greece..

All of those useless symbols made me sick, because I love asymmetricity, the beautiful, but not perfect the abnormal.
Thats why I was happy to find that in Japan people almost dont talk about the number nine, because it is thought it brings pain. Thats why people there dont like to buy something connected to nine and even in hospitals there arent ninth floors.
I started to love that and to think about where people put the stuff they hate or dont need It was the Sewer! It is the place where only rats are living and its a place which no one cares about.

So that was the idea, to show the loneliness and abnormality of number nine in Japan, its rough beauty and mystique.