There's a term called "naturally seductive," which, while carrying some negative connotations, fits Karena perfectly once those negative implications were strip away.
First, her voluptuous figure is inherently alluring. Second, her attire... While she dresses normally in public, she always prefers to wear Roland's clothes or try to be naked in his presence.
In short, she exudes an erotic sensuality from her very core.
As for things like seductive style could be learned and doesn't count as innate?
Then what about her kissing skills?
Roland is certain this is Karena's first kiss. Without sounding narcissistic, she would never kiss anyone but him.
So, this kiss is undoubtedly her first kiss. Yet, despite being a novice, her technique with her lips and tongue is astonishingly skilled, nearly driving Roland wild.
Normally, with the aid of his Massage Technique, Roland is the one who leaves others breathless and weak.