Coming from the perspective of a Vampire: The Masquerade tabletop player, this actually makes perfect sense. They're completely out of touch with humanity or common sense. Especially if they were supernatural to begin with and not just long-lived humans.
that is more, acting like a human, and on that i would agree with you.
But what i am talking about is about 1. emotional maturity; and 2. knowing humans. (knowing humans is not the same as knowing how to act like a human)
To expand on 2. They might be confused about feeling horny(how humans act or feel), but they
should understand that humans are capable of mass violence, of deceit, of vices etc, as well as goodwill.
They should know that humans are capable of irrationality as well as scientific achievements.
They
should have emotional maturity, like patience(an impatient vampire is more likely to draw attention and thus get hunted down and killed) blah blah blah. Knowing emotions and humans are transient.
That Kuro, having observed, failed love lives(her curse is meant to screw up love lives) for generations
should know how fleeting, her attraction is.
That is what it means to be long living and wise.