expression, i-adjective
mean; nasty; selfish; inconsiderate
Colloquial phrase describing a person's character as unpleasant, mean-spirited, or selfish. Often used in casual conversation to criticize someone's personality.
あの人は性格悪いから、あまり関わらないほうがいいよ。
That person has a nasty personality, so you'd better not get too involved.
彼女、性格悪いってよく言われるけど、本当は優しいんだ。
She's often called mean, but she's actually kind.