Frivolous or flashy in appearance or behavior; shallow and often trying to charm or impress others (colloquial, often negative).
彼はチャラい服をよく着る。
He often wears flashy clothes.
あの店員、チャラい態度で話しかけてきた。
That clerk approached me with a flippant/cheesy attitude.
最近の若い俳優はチャラいイメージがある。
Some young actors these days have a flashy/shallow image.