For those who find it relevant, to be brief, nowhere does the Bible anywhere come out and say, premarital sex or intimate touching is forbidden. As Vidiot said, the concern revolved around the notion of possession. The law as described in Ex 22 suggests the seducing and laying of a virgin, might make the guy obliged to marry her if her father demanded it, but only required the compensation of a dowry equivalent if the father finds him objectionable. As damaged goods the father was owed compensation either way. Deut 22 which is basically a rewrite of Ex 22 adds that the guy HAS to marry the girl and can never divorce her as long as he lives. It also adds a story about a guy who marries a girl but who then claims her to not have been a virgin, is really a bizarre one. The parents of the girl are obliged to provide evidence (cloth) that she was a virgin, lest she be stoned at the door of her father's house. Again, the key is that while she was in her father's house she was not to have secretly had sex, putting her father's reputation as the owner of the girl at risk. The story is pretty silly. How did the parents have proof of her virginity (understood as a bloody cloth) without the husband's awareness?? Note that the girl could not provide the proof herself, her testimony wasn't relevant. Further, how hard would it be to provide a cloth with blood on it to save your own reputation and daughter's life?
Like much of the primary history, these rules reflect the often-contradictory sexist views of scribes from the 2nd temple period, and likely never was actually an enforceable code. These writings represented a moral aesthetic not a law as implied.