Umm, no Planar. The Horned God of Wicca has absolutely NO relationship to demons.
This is a good description of what the Wiccan Horned God really is: " The Horned God is the primal, active force within all things, a wild man unfettered by civilization and driven by primal instincts. He is the Lord of the Forest and of animals. He is both hunter and hunted - he who slays so others can live, and he who dies to nourish others in the natural cycle. He rules the season of winter, when the earth is dead and primitive people had to survive by hunting instead of gathering or farming. He represents male sexuality, as the phallic nature of his horns suggest, virility, and strength ."
While some Christians may equate him with the Devil, I think it would be wrong because of this to lead people to believe that the Horned God has anything to do with Satan or with demons.