最さい初しょで最さい後ご

expression, noun which may take the genitive case particle 'no'

first and last; one and only

Emphasizes that something is both the first and the last occurrence, often implying it is a unique, never-to-be-repeated opportunity or event.

• これが最さい初しょで最さい後ごのチャンスだ。

  This is your first and last chance.

• 彼かれにとって最さい初しょで最さい後ごの恋こいだった。

  It was his first and last love.