Typhoid, a food- and water-borne disease strongly associated with the unhygienic life style and environment, is a most prevalent infectious disease in colonial Korea (1910-1945), especially among Japanese imperial settlers. Among them, the residents of Keijo, the impressively modernized capital of the colony, suffered the most. It was an enigma since the city was best equipped with sanitary infrastructures, which way in turn clearly was favored by the famously clean Japanese settlers. This paper examines this enigma of the Japanese imperial hygiene within the political settings of colonial Korea. Especially, it analyzes its relationship with privileges that Japanese imperial settlers had pursued and enjoyed. Living in the Japanese side of the city with properly Japanese style, they indeed enjoyed the up-to-date hygienic and medical infrastructures and interventions like the running water and free vaccines. Yet, the hygienic infrastructure and medical interventions in colonial Korea, like all other modern systems, had their limitations and uncertainties, partly owing to their own profit-seeking business model. The Japanese settlers just made themselves more vulnerable to them in two ways, with their well-discussed identity as “brokers of empire,” if not quasi-rulers. Firstly, as part of the ruling power, they could not acknowledge those limitations of the imperial hygiene that they had helped to create. Secondly, unable to equate themselves with the colonized who were to be disciplined for their unhygienic habits and life styles, they refused interventions that demanded to correct their habits and life styles. Keeping their preferences of “cold tofu” or “sashimi,” and too confident about their imperial regime, these Japanese settlers of Keijo kept their association with that unhygienic disease. This paper displays the vulnerability of Japanese colonial modernity even for its most benefited group while revealing the unique power structure of the Japanese colonial regime, which was built on and sustained by these privileges of unofficial rulers who refused to be disciplined as hygienic subjects.