Birthdate: Jan 19

The hero of 100 years ago and the one who defeated Glen Baskerville. He is revealed to have some sort of connection with Alice's memories and Raven's past. Jack looks uncannily like a grown-up Oz with a long plait. His personality is also quite similar; he does things at his own pace and is loud and cheerful. Oz and Gilbert meet him when they are taken to the Cheshire Cat's dimension.

He is currently residing in Oz's body and can 'possess' Oz and speak through him. When in control, Jack also has full control of Alice's chain power. It is also hinted that he may have feelings for Alice. Jack was the third son of the Vessalius family who was, before the Tragedy of Sablier, a third rate noble family. Thus, with no expectations from his family, he acted quite freely: always smiling, joking and flirting with girls.

Jack is the true instigator of the Tragedy of Sablier. Desperate to see Lacie again, he forced Oz to sever the Chains of the World, thus plunging the city into the Abyss. After this, he framed the Baskerville family for his crime and spread vilifying rumors about the Nightray family.