Title text: I mean, the black-and-white stuff was running backward, but it hardly mattered to the story.
Merlin is a wizard who features prominently in various retelling of the legend of King Arthur. The Once and Future King by author T. H. White is one of the most popular versions of the legend, and in it, Merlin is described as living backwards through time, as Cueball and Megan discuss in this comic (this is also briefly mentioned in the musical Camelot, which is based on this version of the story). In the comic, Cueball is speculating philosophically on how this would have affected Merlin's life as he started life with all his memories, and gradually lost them, comparing this to Cueball's own sense of unreality at goodbyes.
Memento is a movie telling the main parts of its story backwards, while a few black-and-white-scenes are straightforward. So when Merlin watches the movie, he sees nearly the whole story in its actual order, and the title text drives home the joke by noting that the few scenes that make sense to someone with normal perceptions would make less sense to him.
- [Cueball and Megan standing by a train.]
- Megan: I'm bad at goodbyes. At some level I never think they're for real.
- Cueball: They make me think of T. H. White's Merlin.
- Megan: Oh?
- Cueball: He lived backwards, remembering the future and not the past. To him, final goodbyes meant nothing, while first hellos were tearful and bittersweet.
- Megan: Huh - so over the years he'd forget all his friends.
- Megan: Must've been lonely.
- Cueball: Yeah. He ended up just sitting around at home watching DVDs all day. The best was the time he rented 'Memento'...
- [Merlin is sitting in front of a couch, watching TV]
- Merlin: Well, that was straightforward.