Without reading anything after your OP, don't listen to any of these quacks nor do you take advantage of such guest. Be a gentlemen, put on some tunes she would enjoy and watch a comedy movie, play games etc. like typical first time stoners.
Anybody would get a kick and laughs out of that. If you like the lad, I'd suggest you lay off the smoke as long as possible before hand so you can have a lower tolerance to the smoke.
Keep in mind you don't want her to get too stoned to where she can't function.