This has happened to me twice, Vlad has came into my sims' house before uninvited and it was so unexpecting. It has never happened before to me, but I've restarted my entire game like three or four times. I get bored easily! I've gotten texts from Vlad before, but he's never came into my house before.
I'm the type of person, who literally never gets scared of horror movies, haunted houses, and spiders. I get a little into the ghost adventures and ghost hunters shows, but I have never felt more scared in my life when Vlad comes into my house unannounced, decides to drink the blood of my adult sim.