籠かご耳みみ

noun

memory like a sieve; in one ear and out the other

Idiomatic noun describing a person who quickly forgets what they hear, as if their ears are like a leaky basket. Often used self-deprecatingly or to tease someone.

• 彼かれは籠かご耳みみだから、大だい事じなことはメモしておいたほうがいいよ。

  He has a memory like a sieve, so you'd better write down important things.

• ごめん、籠かご耳みみでさっきの話はなしを忘わすれちゃった。

  Sorry, I've got a memory like a sieve and already forgot what you just said.