Dennis and Thomas (first appeared in The Eyes of the Dragon)

Dennis and Thomas is mentioned in the following books:

The Dark Tower II: The Drawing of the Three (May 1987)

One of these men had been a creature the gunslinger believed to be a demon himself, a creature that pretended to be a man and called itself Flagg. He had seen him only briefly, and that had been near the end, as chaos and the final crash approached his land. Hot on his heels had come two young men who looked desperate and yet grim, men named Dennis and Thomas. These three had crossed only a tiny part of what had been a confused and confusing time in the gunslinger’s life, but he would never forget seeing Flagg change a man who had irritated him into a howling dog.
- The Pusher / Chapter 3: Roland Takes his Medicine