skin off one's nose

[skin off one's nose] {n. phr.}, {slang} Matter of interest,concern, or trouble to you. Normally used in the negative.

Go toJake's party if you wish. It's no skin off my nose.

Grace didn'tpay any attention to our argument. It wasn't any skin off her nose.

You could at least say hello to our visitor. It's no skin off yournose.