Really, at 18//19? Even later, that would feel weird for me. Don't you want to know a person better than that before you do it? Or do girls expect that sort of thing? I thought that's exactly what they don't want most of the time. Besides, it's implied they weren't even protected the first time, what if Emi got pregnant? Ugh...
This is the stuff that keeps me up at night thinking. Right here. I really don't get it.
And I guess it's context sensitive then? I just feel like I'd want to wait longer. Being horny is one thing, but self restraint is a virtue.
I find your naivete somewhat endearing. How old are you, if you don't mind answering?
Do you want to know a person better before you do it? Not necessarily. For one thing, you're attaching way too much emotional importance to sex. It is a natural biological thing that humans are programmed to want to do. Personally, I think sex and emotions can (and sometimes should) be kept separate. You can really like someone and not want to have sex with them, and you can really want to have sex with someone but not want anything further than that. If you meet someone and there's a mutual attraction and desire then why wouldn't you go for it? Why would you wait? The moment is right there, right now. It might be a one night stand, it might be friends with benefits, it might be the person you end up spending the rest of your life with.
This is why I worry about very young or inexperienced people seeing KS as a guide of sorts to romance: they're going to develop certain expectations on top of whatever they already have. Personal experience is far, far more important (and fun).
What if she got pregnant? And? That's why the morning after pill exists. That is why coitus interruptus exists. No contraception is 100% effective. You need to talk to your partner and agree about how you want to be safe with them. The same agreement will not apply for any other partners, you'll need to make a different one with them, for both pregnancy (if applicable) and STDs.
Self restraint being a virtue is debatable. This goes back to the whole building up sex into this huge event. Doing so can be unhealthy because your expectations are too high, IMHO. There is no 'perfect' moment, apart from when you are both in the mood and willing, because at the end of the day that's all you need. A slight cautionary note: I've heard of guys who had a girl come on to them, and they turned her down wanting to give the impression of not being just after her for that (you know, the whole nice guy routine) only to find the girl took this as a total rejection and lost all interest in them. In other words: I've had girls tell me they were glad we waited, but when they'd finally wanted to take it to that next level I went along with it. You're only doing a disservice to yourself thinking it's "weird".