The "Things Between" in speculative fiction have more in common because of what they are doing or where they are going, even across the boundaries of fantasy and science fiction -- which are more zones of fading between than hard lines in any case.
Naturally the first genre to pop to mind is Science Fantasy, which has fantasy effects with scientistic names. But Time Travel stories are here because whether the set dressing is scientific or magical, the main problem for the writer is working the changes in time and taking the character through historical or alternate historical settings. The "Things Between" include:
Science Fantasy
Time Travel
Alternate Universes
Humor