When I was growing up, there were certain words in my family that were considered swear words. Surprisingly, when I was serving in Ireland I had a conversation with Elder Pixton about the words I had always considered swear words. He made fun of me because I'd been raised to think "bastard" and "hell" were swear words. Pixton told me that his grandpa lived with his family when he was younger and always used those words in casual conversation. As a result, they weren't considered "swear words", necessarily. I thought it was funny how two people with similar religious backgrounds could be so different when it came to what we considered "right" and "wrong"... or maybe, "acceptable" and "not acceptable". I thought "bastard" was a worse word than "dick" because I'd been raised to think that "bastard" was a swear word and "dick" was a garbage word. That's what we called them. Garbage words. "Dick" was in the same category as "butt hole" and "wiener face".
I guess I shouldn't have been surprised when I found a similar phenomenon with Law of Chastity stuff. Everyone in the church knows that "sex" is wrong when you do it before marriage. But when some people think about "sex", they think about "intercourse". When someone else thinks about "sex", they also include oral sex. So many people in our church have been raised with the same General Conference talks and same church magazine articles, but for some reason... they have different ideas about what is included in the definition of "sex".
It's not that any truly faithful members kid themselves into thinking that only "intercourse" is bad. We all should know that pretty much everything leading up to intercourse should also be avoided... except for vertical cheek and forehead kissing before 11pm in a public place.
I also realize that there is the whole "spirit of the law" vs "letter of the law". I don't know for certain, but I can imagine the Bishop's Handbook has very specific guidelines about how a bishop is supposed to handle intercourse out of wedlock. But I doubt the handbook is specific regarding every single moral and sexual transgression. It's probably just a series of suggestions... letting the bishop decide, with the help of the Spirit, how to handle any given situation. So I don't even know that bishop's, themselves, have phrases and terms followed by specific definitions of what each action is comprised of. That would actually be pretty gross.
So can a person engage in oral sex and still consider themselves a virgin? Some people would laugh at the thought. Of course he's not a virgin. He got a B.J.! But what if that person has never considered oral sex as "sex"? He's always purposely refrained from having sex, telling himself that he wants to be a virgin when he gets married. Does his definition matter at all? Or is it only your definition that matters?