“Who cares?” in Japanese
Short answer
Who cares? in Japanese is “構うものか” (kamaumonoka). Full meaning: who cares?, I don't give a damn, what does it matter?.
Other ways to say “Who cares?” in Japanese
知るものか
shirumonoka who cares?, see if I care, who knows?, how should I know?
誰得
daretoku who benefits (from that)?, who cares?, who would want that?, who is it meant to appeal to?; pointless, of benefit to no one, of interest to no one, appealing to no one, extremely niche
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