Microstory 90: One True Mate

This is a microstory. You'll have to read it to find out what it's about.

There is another universe, right next to ours. It wasn’t ever supposed to be so close. The void between universes is designed to be immeasurably large, but due to a little human ingenuity, and one or two cataclysmic accidents, theirs and ours were brought closer together. This caused significant problems for our God, but that is another story. The interesting thing about these travelers is their biology. They were, in almost all respects, human. In fact, being the rightful humans who evolved legitimately in their universe, they were considered pure. But there was an aspect of their reproduction that, all things being equal, made them unique. When a male and a female copulate for the first time, they are inextricably connected. Certain chemicals are released in each other’s bodies that prevents each from reproducing offspring with any other partner, which means that there is no such thing as a half-sibling. Other chemicals are released in their brains that tighten a psychological and emotional bond between the two. A final, and extremely mysterious, process occurs at the same time. The two mates are linked by time and their lives. If one dies, the other will die as well. When the relatively small population was drawn towards our universe, most of them lost their mates to the void; with only a handful of couples surviving together. Not long after arrival, one such of these lucky couples was torn apart by a machine that propelled one of them into the future. The other was left immortal, doomed to spend the rest of his days waiting for his true love’s return. Gavix doesn’t know that his mate will one day return to him. He knows only that he has been alone for [redacted] years.