尻しり抜ぬけ

noun

forgetfulness; leaving things unfinished

Describes a person who starts things but doesn't finish them, or who forgets things easily. Often used in a mildly critical or teasing way.

• 彼かれは尻しり抜ぬけで、仕し事ごとを最さい後ごまでやり遂とげたことがない。

  He's a forgetful person who never finishes his work.

• あの人ひとはしりぬけだから、約やく束そくを忘わすれているかもしれない。

  That person is forgetful, so they might have forgotten the promise.