Yea. I was a bit inspired by stumbling upon a nice picture of Wendy and Abagail from the game Don't Starve. If you don't know, Wendy is living while Abagail is dead, but Abagail haunts Wendy. It is similar to Dean's character. Wendy can see Abagail and talk to her but Abagail is mute. Wendy herself can't do much outside of asking Abagail for help. Abagail can touch the physical world and can bring the temperature down to freezing levels. You know how like ghosts tend to cause that cold feeling.
There is more, however, and Wendy can swap planes with Abagail. Doing so allows Wendy to experience the plane of the dead, allowing her to interact with spirits and such. Meanwhile, Abagail can interact with the physical world in a much greater capacity. In fact, she is rather savage and has an unnatural level of strength, speed, and doesn't really care for pain, but can get injured. Abagail is still mute and really only wants to rip apart anything living. Exposure to each other's planes is pretty taxing, though, and dangerous. The twins can not use this to phase traverse through physical barriers as switching planes requires the mortal body to touch the spiritual body.
And that's really it. Their names probably won't be Wendy and Abagail, but you can see the similarities. They might not even be twins as I have an idea for something else. A split personality sort of thing.