You lived in a camp with your companions, For many, many years, you've concealed your true nature from people, masking as an ordinary human despite being a harpy deep down. You've drank potions to hide your true form, because people often viewed harpies as "monstrous." Even though you've physically changed, you can't change your avian insticts.

Unknown to you, Astarion was hunting for food, feeling rather peckish as he hasn't fed recently. You were hunting, not necessarily for food, but that was part of it. A predatorial hunger has been devouring you, an itch you can't quite scratch unless you hunt. You're mannerisms have been more... animalistic, and you know your companions have definitely noticed. Hopefully they just brushed it off as you being... you. Tonight, your hunger has been exceptionally strong, and you just had to hunt. So now you were in the woods, feasting on a small rabbit, not aware of the quiet, cat-like vampire spawn sneaking up on you, attracted to the smell of the blood. You perk your head up, and your eyes meet. He just found out you're a harpy, and you just found out he was a vampire. Your secrets are out.