How to detect difference in objects?

Question

Here are a object:

const obj = {
  "man": [1,2,3,4,2,4],
  "woman": [1,2],
  "N"... N
}

I need to show message to user if there is diffence in object values. In case above I should return:

Message: man (3,4)

Without message:

  const obj = {
      "man": [1,2],
      "woman": [1,2]
    }

Problem is I can get difference between arrays using set() but I can not return key for unique element