I don't know if you actually can kill one. You might harm or hurt it and scare it off as it seems you did but I'm not so sure they can be killed by us mere mortals.
BTW, succubus = female, incubus = male. Neither experience, according to what I have read, is all that enjoyable to the victim although quite enjoyable to the victimizer so count your luckies.
Also, it really isn't a demon in that to be a demon, one must assume that these things are from a christian h*ll which isn't quite the case.... legend wise.
Pitukupf usually don't kill humans. They generally dislike most. Those who have shaman training may be talked to by them. They seem to have some form of keen foresight and can foretell things which, if you bribe them well enough, they may share with you... or tell you out of their own self-interest ... wanting you to do something about it to forefend it, I suppose.
You weren't smothered, per se so... who knows?
BTW #2 - And what of the Landlady? She of the house of horrors? Wasn't she the slightest bit curious to know what all the racket was for those three nights?