The act?...Meh, fifty fifty. In all honesty, it depends on certain factors.
I would smack myself a few times as if I was pepping myself up to talk to them because I was tired, but I would actually be testing to see if I was awake or not. I would then analyze the situation.
Male, female, or possibly trans? Doesn't matter, pansexual.
Age? Looking older than 35? Creepy. Younger than 16? Probably a prank.
Location? Right in front of my house? Kind of creepy...
Any cameras? No? Also kind of creepy.
If my analysis concluded that it wasn't nearly as bad as it seemed, I would be relieved, and speak to them. If it concluded it was incredibly creepy, I would continue to analyze it.
If I then determine they are probably stalking me, the age of the person, and how feminine they are come into play. Male, female, or trans? Doesn't matter. Pansexual. Under 35, but over 17? More feminine than masculine, long-hair, etc.?
Conclusion: Unbridled glee at finally having my own stalker. Something I've kind of always wanted on some deep, dark, crazy level.