The other tantras also say when someone uses the finger to point at the moon, we should look at the moon, not the finger. Similarly, we should not obsess with the appearance of the yab-yum deities or how they are depicted, but rather focus on the underlying significance—the inseparability of clear light and emptiness that is the core and essential view in tantra. The yab-yum image is like a language, sign, or illustrated dictionary that uncovers the real meaning of the union of clear light and emptiness.
~Depicted from GATEWAY TO VAJRAYANA PATH - Vajrayana Terminology