[Wow. Both of these topics piss him off on some level. But at least he knows something about them.]

Vampires are... parasites. Nasty business. Messing around with them will only get you in trouble. They drink blood, especially human blood, and cutting off their head usually kills them. The only problem is, there are lots of different kinds of vampires. So maybe that's not true for all of them.

... As for marriage, just make sure it will work out. And don't get married for someone else's sake.