It's not the same if the one-night stand hasn't met the non-possessed host before, because in that case they've only spoken to the angel; the only aspect of the host that's involved, from their perspective, is his physical appearance.

Also, what angels seem to generally do is possess one body and then use that body for all their purposes on Earth, so the host would be possessed at all times (not sure what would happen when the angel wasn't on Earth; they seem to disappear, host body and all, when they leave) and there would be no awkward conversations (for the host, at any rate). If the host were thinking 'hey, that's my old boss', though, I'm sure Ithuriel would be able to pick up on that and avoid potentially uncomfortable sexual situations. (Or deliberately pursue them, just for his own amusement.)