The lupo that stopped Emma from leaving Storybrooke has not been dato an identity, but we have been dato clues enough to determine it. In a sneak peek for tonight's episode,Graham is often featured with one lupo as his companion. In another sneek peak,the Evil Queen later reveals that he was raised da wolves. Since everyone in the fairy tale land was affected da the curse,even animals, I believe that the lupo that kept Emma from leaving is the same lupo that was Graham's ally and that possibly raised him.