This is Jack's uncle.

Let's say the university he got the degree in burnt after he got out, killing all the people there were inside. He decided to get inside for a bit just for the last goodbye, when with an exhale of a smoke, he got all the ghosts of it's inmates in his lungs.

Strange, huh? Well, now apart from a doctor he periodically does sessions in the city theatre, letting his ghosts answer things about the future.

It was rather inspired by some Hellboy character who happened to have the same deal. This is some vector-like goodness.

EDIT: I remember now: it was Mr. Tod from Hellboy.