口くちが曲まがる

expression, godan verb (-ru)

incur divine punishment; get into trouble for speaking ill

Idiomatic expression: literally 'one's mouth becomes warped', used to warn that speaking badly of others will bring misfortune or divine retribution. Often used in admonitions.

• 人ひとの悪わる口ぐちを言いうと口くちが曲まがるよ。

  If you speak ill of others, you'll get into trouble.

expression, godan verb (-ru)

warp one's mouth; have a crooked mouth

Literal meaning: the mouth becomes physically distorted or twisted. Rarely used outside the idiomatic sense; may appear in descriptive or medical contexts.

• 事じ故この後あと、彼かれは口くちが曲まがってしまった。

  After the accident, his mouth became crooked.