Never admit to not being a virgin or talk about previous boyfriends unless he asks. If he asks, downplay it as much as possible and make it sound like something that probably just involved fingering and act embarrassed and refuse to talk about it further. You wouldn't buy a used pillowcase if you know it's been jizzed on hundreds of times and no good quality guy wants to marry a girl if he knows she's been jizzed on by other guys. Also don't worry about inducing boob growth, tiny boobs are the best boobs.