You can go check out the link yourself and play the video; my opinion is that these lion cubs are merely tasting the human.
Many animals come with what we think are human emotions; the problem with this thinking is that it ignores the fact that this is an animal that, in the wild, has the instinctual need to eat meat.
Time Magazine has a near-annual fixation on animals, emotions, and whether they think like humans do. Let's cut the crap. Animals are animals, and they are unpredictable. One minute, they're kissing on you, the next minute, they have your arm in their mouth and there's blood everywhere.