This is a fairly fun platformer. The grapple is fun to use, although crazy powerful since it seems to have unlimited reach, meaning players don't have to be very thoughtful about how to use it. I liked the character's wall cling and climb animation.
I like the intro story, but I think you're missing capitalization on some of the names.
I like the sprawling branching level in which you don't really know what path to take. However, I think the level could be improved by making the branches more clearly visible when you're nearby. In particular, if there's an opening in the ceiling to ascend through, and I'm not near a wall, make the ceiling lower so I can see the opening from the ground, because otherwise I'll likely just run past without any reason to stop and try to climb up.