Here is my idea:
We are college freshman. I'm dating your room mate who has led a very sheltered life. Only male she's ever seen nude is her baby brother when he was in diapers.
You know we are getting really close to having sex for the first time, and you want to make sure I'll be a total gentleman, and not be the kind of person who is just wanting to deflower and run.
Hope this is enough details to get started. If your interested please PM me.