Sticking out the tongue is thought of as clever in some circles, very few of which include Rhinos. Derision and face-making are frowned upon, except in highly stressful situations.
At Your Inner Rhino, We seldom stick out our tongues, and assume our Readers don’t either. In a pinch, a Rhino might stoop to an “Oh, Yeah?”.
(Some Hints are more heavy-handed than others.)