The Earl goes to people who have just lost someone they love and tells them he can give them back. If they say yes... he forces the ghost to kill the person who loved them and live within their body.

[It's a monstrous act. So much so that say that feels redundant. He touches his left eye for a moment.]

No, they can't. That's why Exorcists wear this uniform. Akuma are driven to try to kill Exorcists, so we draw their attacks as much as we can. [As most Exorcists can't see the Akuma until after they evolve into a more monstrous form, they're often a bit jumpy.]