Hover hand usually takes place in photos at conventions when a nervous nerdy guy is posing with an attractive female actress or model. They usually rap their arm around the chicks back and have their hand hover over the females shoulder or waist, afraid to touch them.
Jeff: Hey Drew! Check this picture, bro! This dude has his hand barely touching this super hot chick's waist like a creep. Why doesn't the he just touch her?
Drew: HAHA! What a small dick, faggot. I hate people who hover hand. I'd put my whole hand around her waist and have my thumb damn near hanging on on the rim of her jeans.