Effect of using Two of a Kind or Favor on an empty hand in Exploding Kittens?
You have it right: the selected player gives you nothing. Whether you want to restrict playing the card (or pair) in that way (to no effect) is up to you (EK is not the kind of game to get official answers on such things), but since playing the card/pair that way is only bad for the player playing it, the restriction won't come up.