Samidaresou is the two-storey, reinforced-concrete and dilapidated block of flats numbered 1 to 6. Shinkuro lives the flat 5 of Samidaresou. There are no bathrooms and instead of it, a joint toilet is furnished. The dimensions of every flat are about 9.72 square metres. The supervisor doesn't always stay and neglects its management. So, residents must even negotiate slight troubles and for its usefulness. And there is an implicit rule which prohibits to snoop neighbour's individual affairs respectively. Else residents without Shinkuro are not unknown. When residents leased flats, they agreed in which anything happened in each flat is unchallenged, even if any sort of criminals happened. Residents are hardly to interact each other. In its estate, it forbids any combats and Akuu Company cannot even combat in the estate. Any burglars, housebreakers even dealers and recruits of newspaper and religion are repelled from the estate. Even though Samidaresou's rule concerns, Ryuji abuses Murasaki and Shinkuro fights "Tetsuwan" in the estate. When and who enacted the rule? And who takes the transactions to violators? These questions are not answered.