The horn just means you have the fucking horn! Having the horn refers to a want in sexual desire. The horn-bearer wants it. Sluts have the horn and will take such horn. Most guys have the horn as general rule. If out at bars its always a horn-off, (often referred to as flirting), yet one must be cautious in horn judgement as its never true love. The horn for males can extend to various and great lengths.
A hand gesture used by metal heads to symbolize their love of the music. First used by Ronnie James Dio during his years in Black Sabbath, during the Heaven and Hell tour.
Dio would use the horns to emphasize a particularly dark moment. The moment had to deserve the horns. Dio himself did not invent the sign, the horns were originally an italian gesture that was used either to repel or to give the evil eye, and went by the name Mano Cornuto. Dio gives the credit to his grandmother for impressing the horns upon him, for she was the one who used it the most around him.