Straight edge? HA!
In other words - No, I'm not. Plus, I believe that sex is a man and a woman becoming one, whole thing. There's no reason why it should be AFTER marriage, because it's a spiritual, emotional, and physical bond. There's nothing shameful about it; thus, I believe there's no reason for it to be held until after marriage.
*I believe.
No comment on drugs, smoking, and drinking.