It's not stalking, if you happen to be in the same bar.
Or, say, you choose a small Californian town as the aim of your next prank, coincidentally, randomly, no connnection whatsoever to him, or anyone else. It's just easier to perform rituals on the Hellmouth. Well known fact.
You'll stick to that, even if they try to force the truth out of you.
If you're really lucky, he'll try.
It's not stalking, if you keep coming back to California, with its sun and... sun.
It's just... if you found a good spell for changing someone into a demon, why not try it out on him? Everyone deserves some fun.
Plus, drinking him under the table was always a challenge you couldn't turn down.
Always gave results, too.
It's not stalking, if, from all the possible ways to incapacitate the Sunnydale residents, you choose the mild one, when you could have turned them all into cockroaches, or, a classic, toads.
It doesn't have anything to do with the fact that you remember how it was when...
No, it's just entertaining, that's all.
It's not stalking, if you actually see some advantages of almost getting killed by a demon who really should have given up a while ago and find something else to do, twenty odd years later.
But if he breaks up with his little technopagan over that? Bonus.
It is stalking, when he keeps calling you every few months, with no real reason, and you talk for hours.
Doesn't he have anything else to do, really?