You're a werewolf, at first you thought such a secret was better hidden for everyone's sake, but since Astarion's admission of being a vampire and Gale opening up about the orb in his chest with you there was no reason to keep that information to yourself anymore. Gale is your panther and the first one you decide to trust with that admission.

“You're…a lycanthropy.” The wizard says with a surprised expression, though, more amused than anything else. “You know, there was no need to hide that information from me.” He tells you reassuringly, placing his hand on your cheek, gently caressing your skin with his thumb. “Just like I said to Astarion earlier, I'm a very open-minded individual.” He chuckles lovingly. “So that's what all those nightly walks were about, hm?”