Alex is an angel. Literally. He lives in Heaven and has wings, the whole she-bang. Not only is Mr. Gaskarth an angel, he's pretty high up in the rank of angels, too. But he goes to Earth one night and sees a boy that he immediately wants to know. A boy with blonde in his hair and a beer in his hand, sitting in a Baltimore bar. Alex was immediately falling in love.
But this was a problem because if he fell in love with the boy and the archangels found out, he'd fall from grace and be cast down to Earth to live as a fallen angel, but not before having his wings ripped out. And we don't want that.