unfinished business

Noun

uncountable

A matter that still has to be completed or dealt with, sometimes with an ominous or threatening implication.

Japanese Meaning

未解決の問題、すなわち解決や処理がなされていない事柄 / 未整理の課題、今後対処すべき残された事項

The detective returned to the old house, convinced there was unfinished business waiting in the shadows.

探偵は古い屋敷に戻り、影の中に未解決の問題が潜んでいると確信していた。

Sense（1）

A matter that still has to be completed or dealt with, sometimes with an ominous or threatening implication.